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INTRODUCTION: This publication represents a massive revision of theRhododendron Species Dictionary published in 1984 and made available through the Rhododendron Species Foundation. That publication was described as listing clones, valid and invalid synonyms, varieties, sub-species and species, but excluding sectionVireya. Since that time extensive revision has taken place in the genus. This publication attempts to encompass those revisions and now includes sectionVireya. The revision of the GenusRhododendron by the Royal Botanic Garden Edinburgh, Scotland has been essentially completed. This monumental task has been published in a series of monographs and then summarized in the publication: Chamberlain, et al.,The Genus Rhododendron, Its classification & synonymy, The Royal Botanic Garden Edinburgh, Enverleith Row, Edinburgh, Scotland, 1996. At the time of the 1996 publication the genus numbered 1,025 recognized species. With the passage of time, more explorations and more research, species will be added and species will be lumped. It is an ever-changing scene. I have even found changes between the summary published in 1996 and the revision of the Subgenus Tsutsusi published in 1990. For these reasons this effort is obsolete at the time that you read it, but it is hoped that it will be useful for some years to come. For details about the genus and its revisions you are referred to the following publications in addition to the one listed above:

CHAMBERLAIN, D.F. (1982). A revision of Rhododendron. 11. Subgenus Hymenanthes.Notes from the Royal Botanic Garden Edinburgh. 39(2): 209-486.

CHAMBERLAIN, D.F. & RAE, S.J. (1990). A revision of Rhododendron. IV. Subgenus TsutsusiEdinburgh Journal of Botany. 47(2): 89-200.

CULLEN, J. (1980). A revision of Rhododendron. 1. Subgenus Rhododendron sections Rhododendron and Pogonanthum.Notes from the Royal Botanic Garden Edinburgh. 39(l): 1-207.

JUDD, W.S. & KRON, W.S. (1995). A revision of Rhododendron sections Sciadorhodion, Rhodora and Viscidula.Edinburgh Journal of Botany. 52(l): 1-54.

KRON, K.A. (1993). A revision of Rhododendron section Pentanthera.Edinburgh Journal of Botany. 50(3): 249-364.

PHILIPSON, W.R. & PHILIPSON, M.N. (1986). A revision of Rhododendron. 111. Subgenera Azaleastrum, Mumeazalea, Candidastrum and Therorhodion.Notes from the Royal Botanic Garden Edinburgh. 44(l): 1-23.

No significant revision of clonal names has been made since the 1984 edition. Even though such names may be registered as a named species, there is seldom qualified documentation that named clones are indeed species plants and not horticultural or wild hybrids. Although I have included the 1984 names I have abandoned the effort to include additional clonal names. The problem is well illustrated by the recent discussions about the probable hybrid 'Ken Janek' that has often been considered a named clone of R. degronianum ssp. yakushimanum var.yakushimanum.

In this document the hierachical names are shown in bold face type in their first entry. No effort is made to include the authority for any of the taxa, as that is not the purpose of this dictionary. Reference should be made to the botanical literature sited for such information. The current hierarchy of genus Rhododendron is as follows:

Rhododendron 
   Subgenus Azaleastrum 
      Section Azaleastrum
      Section Choniastrum
   Subgenus Candidastrum 
   Subgenus Hymenanthes 
      Section Ponticum 
        Subsection Arborea 
        Subsection Argyrophylla
        Subsection Auriculata 
        Subsection Barbata
        Subsection Campanulata 
        Subsection Campylocarpa
        Subsection Falconera 
        Subsection Fortunea
        Subsection Fulgensia 
        Subsection Fulva 
        Subsection Glischra
        Subsection Grandia
        Subsection Griersoniana 
        Subsection Irrorata
        Subsection Lanata 
        Subsection Maculifera
        Subsection Neriiflora 
        Subsection Parishia 
        Subsection Pontica 
        Subsection Selensia
        Subsection Taliensia
        Subsection Thomsonia 
        Subsection Venatora
        Subsection Williamsiana 
   Subgenus Mumeazalea 
   Subgenus Pentanthera
      Section Pentanthera 
      Section Rhodora. 
      Section Sciadorhodion 
      Section Viscidula 
   Subgenus Rhododendron
      Section Pogonanthum 
      Section Rhododendron 
        Subsection Afghanica 
        Subsection Baileya 
        Subsection Boothia
        Subsection Camellfiflora 
        Subsection Campylogyna 
        Subsection Caroliniana 
        Subsection Cinnabarina 
        Subsection Edgeworthia 
        Subsection Fragariflora 
        Subsection Genestieriana 
        Subsection Glauca 
        Subsection Heliolepida 
        Subsection Lapponica
        Subsection Ledum 
        Subsection Lepidota 
        Subsection Maddenia 
        Subsection Micrantha 
        Subsection Monantha 
        Subsection Moupinensia
        Subsection Rhododendron 
        Subsection Rhodorastra 
        Subsection Saluenensia 
        Subsection Scabrifolia
        Subsection Tephropepla 
        Subsection Trichoclada 
        Subsection Triflora 
        Subsection Uniflora 
        Subsection Virgata
      Section Vireya 
        Subsection Albovireya 
        Subsection Malayovireya 
        Subsection Phaeovireya
        Subsection Pseudovireya
        Subsection Siphonovireya
        Subsection Solenovireya 
        Subsection Vireya 
   Subgenus Therorhodion 
   Subgenus Tsutsusi
      Section Brachycalyx 
      Section Tsutsusi

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aberconwayi sp. in subsection IRRORATA
aberconwayi clones
     'His Lordship'
     'Westhaven'
aberrans syn. R. traillianum var. traillianum
abietifolium sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
achroanthum syn. R. rupicola var. rupicola
acraium syn. R. primuliflorum
acrocline syn. R. culminicolum var nubicola
acrophilum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
acuminatum sp. in subgenus RHODODENDRON section VIREYA subsection MALAYOVIREYA
acuminatum syn. R. mucronulatum
acuminatum var. of R. mucronulatum syn. R. mucronulatum
acutifolium f. of poukhanense syn. R. kaempferi x R. macrosepalum
adamsii syn. R. fragrans
adansonii syn. R. ponticum
adenogynum clones
     'Kristy'
adenogynum sp. in subsection TALIENSIA
adenophorum syn. R. adenogynum
'Adenophorum Group' syn. R. adenogynum
adenopodum sp. in subsection ARGYROPHYLLA
adenostemonum syn. R. irroratum ssp. pogonostylum
adenostylosum var. of R. oreodoxa var. sp. in subsection FORTUNEA
adenostylum var. of R. medoense syn. R. ngawchangense
adenosum sp. in subsection GLISCHRA
adenosum var. of R. glischrum syn. R. adenosum
adinophyllum sp. in subgenus RHODODENDRON section VIREYA subsection PSEUDOVIREYA
admirabile syn. R. lukiangense
adoxum syn. R. vernicosum
adroserum syn. R. lukiangense
aechmophyllum syn. R. yunnanense
aemulans var of Azalea viscosa syn. R. viscosum
aemulans var of R. viscosum syn. R. viscosum
aemulorum syn. R. mallotum
aequabile sp. in subgenus RHODODENDRON section VIREYA subsection ALBOVIREYA
aeruginosum syn. R. campanulatum ssp. aeruginosum
aeruginosum ssp. of R. campanulatum ssp. of sp. in subsection CAMPANULATA
aeruginosum var. of R. campanulatum syn. R. campanulatum ssp. aeruginosum
'Aestivale' clone of cinnabarinum ssp. cinnabarinum
aestivale f. cinnabarinum syn. R. cinnabarinum ssp. cinnabarinum
AFGHANICA (subsection) Subsection in subgenus RHODODENDRON
afghanicum sp. in subsection AFGHANICA
aganniphoides var. of R. balfourianum var. of sp. in subsection TALIENSIA
aganniphum syn. R. aganniphum var. aganniphum
aganniphum var. aganniphum var. of sp. in subsection TALIENSIA
aganniphum var. flavorufum var. of sp. in subsection TALIENSIA
aganniphum var. glaucopeplum syn. R. aganniphum var. aganniphum
aganniphum var. schizopeplum syn. R. aganniphum var. aganniphum
agapetum syn. R. kyawi
x agastum R. decorum x arboreum ssp. delavayi
agastum var. pennivenium syn. R. tanastylum var. pennivenium
agathodaemonis sp. in subgenus RHODODENDRON section VIREYA subsection SIPHONOVIREYA
agathodaemonis syn. R. herzogii
agetum syn. R. neriiflorum ssp. agetum
agetum ssp. of R. neriiflorum ssp. of sp. in subsection NERIIFLORA
agetum var. of R. neriiflorum syn. R. neriiflorum ssp. agetum
agglutinatum syn. R. phaeochrysum var. agglutinatum
aiolopeplum syn. R. phaeochrysum var. levistratum
aiolosalpinx syn. R. stewartianum
aiolosalpinx var. of R. stewartianum syn. R. stewartianum
aischropeplum or ?aishropeplum syn. R. roxieanum var. roxieanum
aizoides ssp. of R. sanguineum syn. R. sanguineum ssp. sanguineum var. himertum
alabamense sp. in subgenus PENTANTHERA section PENTANTHERA
alba var. of Azalea nudiflora syn. R. periclymenoides
alba var. of Azalea periclymenoides syn. R. periclymenoides
albertsenianum sp. in subsection NERIIFLORA
albicaule syn. of R. fortunei ssp. fortunei
albidum f. of R. roseum syn. R. prinophyllum
albiflorum var. of R. reticulatum syn. R. reticulatum
albiflorum var. of R. rhombicum syn. R. reticulatum
albiflorum var. of R. serpyllifolium syn. R. serpyllifolium
'Albiflorum' clone of serpyllifolium
ALBIFLORUM (series) syn. subgenus CANDIDASTRUM
Albiflorum Lanciniatum syn. R. hirsutum
albiflora f. of rhodora syn. R. canadense
albiflorum f. of R. canadense syn. R. canadense
albiflorum f. of R. citrinum syn. citrinum var. citrinum
albiflorum f. R. schlippenbachii syn. R. schlippenbachii
albiflorum var. of R. dauricum syn. R. dauricum
albiflorum var. of R. mucronulatum syn. R. mucronulatum var. mucronulatum
albiflorum var. of R. simsii var. of sp. in subgenus TSUTSUSI section TSUTSUSI
albiflorum only sp. in subgenus CANDIDASTRUM
albiflorum var. albiflorum var. of sp. in subgenus CANDIDASTRUM
albiflorum var. warrrenii var. of sp. in subgenus CANDIDASTRUM
'Albion Ridge' clone of macrophyllum
albipetalum ssp. of R. temenium syn. R. eudoxum var. eudoxum
albomentosum (tentative) var. of R. arboreum ssp. delavayi var. of ssp. of sp. in subsection ARBOREA
alborugosum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
ALBOVIREYA subsection in section VIREYA
albrechtii clones
     'Michaeì McLaren'
albrechtii sp. in subgen. PENTANTHERA section SCIADORHODION
'Album' clone of rigidum album
album f. of R. arboreum ssp. cinnamomeum var. roseum form of var. of ssp. of sp. in subsection ARBOREA
album f. of R. nudiflorum syn. R. periclymenoides
album f. of R. periclymenoides syn. R. periclymenoides
album f. of R. serpyllifolium syn. R. serpyllifolium
album f. of R. vaseyi syn. R. vaseyi
album sp. in subgenus RHODODENDRON section VIREYA subsection ALBOVIREYA
album syn. R. albiflorum
album syn. R. aequabile
album syn. R. zollingeri
'Album' syn. R. arboreum ssp. cinnamomeum var. roseum
album var. of R. anthopogon ssp. anthopogon var. of ssp. in section POGONANTHUM
album var. of R. kesangiae var. of sp. in subsection GRANDIA
album var. of R. maximum syn. R. maximum
album var. of R. nudiflorum syn. R. periclymenoides
album var. of R. arboreum syn. R. arboreum ssp. cinnamomeum var. roseum
album var. of R. glaucophyllum ssp. glaucophyllum var. of ssp. of sp. in subsection GLAUCA
album var. of R. lepidotum var. of sp. in subsection LEPIDOTA
album var. of R. maximum syn. R. maximum
album var. of R. thomsonii syn. R. thomsonii ssp. thomsonii
album var. of R. vaseyi syn. R. vaseyi
algarvense syn. R. ponticum
alpicola syn. R. nivale ssp. boreale
alpinum var. of R. saruwagedicum syn. R. saruwagedicum
alternans sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
alticolum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
alutaceum syn. R. alutaceum var. alutaceum
alutaceum var. alutaceum var. of sp. in subsection TALIENSIA
alutaceum var. iodes clones
     'White Plains'
alutaceum var. iodes var. of sp. in subsection TALIENSIA
alutaceum var. russotinctum clones
     'Easter Island'
alutaceum var. russotinctum var. of sp. in subsection TALIENSIA
amabile sp. in subgenus RHODODENDRON section VIREYA subsection SOLENOVIREYA
amagianum f. of var. heptamerum of ssp. heptamerum of sp. degronianum in subsection PONTICA
amagianum f. of R. metternichii syn. R. degronianum ssp. heptamerum var. kyomauruense f. amagianum
amagianum sp. in subgenus TSUTSUSI section BRACHYCALYX
amagainum var. of weyrichii syn. amagianum
amakusaense sp. in subgenus TSUTSUSI section BRACHYCALYX
amakusaense var. of viscistylum syn. amakusaense
amamiense syn. R. latoucheae var. latoucheae
amandum sp. in subsection MADDENIA
amanoi ssp. of R. scabrum sp. in subgenus TSUTSUSI subsection TSUTSUSI
amanoi syn. R. scabrum ssp. amanoi
amaurophyllum syn. R. saluenense ssp. saluenense
ambiguum clones
     'Jane Banks'
ambiguum sp. in subsection TRIFLORA
amesiae sp. in subsection TRIFLORA
amoenum syn. R. kiusianum 'Amoenum'
'Amoenum' clone of R. kiusianum
'Amoenum Coccineum' clone of R. kiusianum
amoenum form of obtusum syn. R. kiusianum 'Amoenum'
amoenum var. of kiusianum (amoenum f. japonicum) syn. R. kiusianum var. kiusianum
amoenum var. of R. indicum syn. R. obtusum
amphichlorum ? variant of campylogynum or sp. in subsection CAMPYLOGYNUM
   amundsenianum sp. in subsection LAPPONICA
anagalliflorum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
andersonii syn. R. variolosum var. andersonii
andersonii var. of R. variolosum var. of sp. in subgenus RHODODENDRON section VIREYA
'Angel' clone of degronianum ssp. yakushimanum var. yakushimanum
angiense syn. R. culminicolum var. angiense
angiense var. of R. culminicolum var. of sp. in subgenus RHODODENDRON section VIREYA
angulatum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
angustifolium f. of hirsutum syn. R. hirsutum
angustifolium f. of metternichii var. pentamerum syn. R. makinoi
angustifolium ssp. of R. stenophyllum ssp. of sp. in subgenus RHODODENDRON section VIREYA
angustifolum var. of R. stenophyllum syn. stenophyllum ssp. angustifolium
syn. stenophyllum ssp. angustifolium
ankaii var of R. degronianum syn. R. degronianum ssp. degronianum
'Anna Strelow', A.M. 1979 clone of annae
annae clones
     'Anna Strelow'
     'Folk's Wood'
annae sp. in subsection IRRORATA
annae ssp. laxiflorum syn. R. annae
annamense syn. R. simsii var. simsii
'Annapurna' A.M. 1974 and 1979 clone of anthopogon ssp. hypenanthum
ANTHODENDRON (subgenus) syn. genus RHODODENDRON subgenus TSUTSUSI
ANTHODENDRON syn. genus RHODODENDRON subgen. PENTATHERA
Anthodendron nudiflorum syn. R. periclymenoides
Anthodendron ponticum syn. R. luteum
Anthodendron viscosum syn. R. viscosum
ANTHOPOGON (series) syn. with section POGONANTHUM
anthopogon syn. R. anthopogon ssp. anthopogon
anthopogon ssp. anthopogon clones
     'Annapurna'
     'Betty Graham'
anthopogon ssp. anthopogon ssp. of sp. in section POGONANTHUM
anthopogon ssp. anthopogon var. album var. of ssp. in section POGONANTHUM
anthopogon ssp. anthopogon var. hypenanthum syn. R. anthopogon ssp. hypenanthum
anthopogon ssp. hypenanthum ssp. of sp. in section POGONANTHUM
anthopogon var. haemonium syn. R. anthopogon ssp. anthopogon
anthopogonoides ssp. anthopogonoides ssp. of sp. in section POGONANTHUM
anthopoganoides ssp. hoi ssp. of sp. in section POGONANTHUM
anthosphaerum sp. in subsection IRRORATA
anthosphaerum var. eritimum syn. R. anthosphaerum
anwheiense sp. in subsection MACULIFERA
anwheiense ssp. of R. maculiferum syn. R. anwheiense
'Aola' clone of valentinianum
aperantum sp. in subsection NERIIFLORA
aperantum var. subpilosum syn. R. aperantum
apiculatum syn. R. concinnum
apoanum sp. in subgenus RHODODENDRON section VIREYA subsection MALAYOVIREYA
apodectum syn. R. dichroanthum ssp. apodectum
apodectum ssp. of R. dichroanthum ssp. of sp. in subsection NERIIFLORA
apodectum var. of R. dichroanthum syn. R. dichroanthum ssp. apodectum
appropinquans ssp. of R. floccigerum syn. R. neriiflorum ssp. phaedropum
appropinquans var. of R. floccigerum syn. R. neriiflorum ssp. phaedropum
apricum sp. in subgenus TSUTSUSI section TSUTSUSI
apricum var. falcinellum syn. R. rufulum
arachnoideum var. of R. glischroides syn. R. glischrum ssp. glischroides
araiophyllum ssp. araiophyllum clones
     'George Taylor'
araiophyllum ssp. of araiophyllum ssp. of sp. in subsection IRRORATA
araiophyllum ssp. lapidosum ssp. of sp. in subsection IRRORATA
araliiforme syn. R. vernicosum
ARBOREA (subsection) subsection in subgenus HYMENANTHES
arborescens sp. in subgenus PENTANTHERA section PENTANTHERA
arborescens var. richarsonii syn. R. arborescens
arboreum ssp. arboreum clones
     'Blood Red'
     'Dr. Bowan'
     'Goat Fell'
     'Henry Shilson'
     'Holder Hall'
     'John Skrentny'
     'Riviera Beauty'
     'Rubaiyat'
arboreum ssp. arboreum ssp. of sp. in subsection ARBOREA
arboreum ssp. cinnamomeum ssp. of sp. in subsection ARBOREA
arboreum ssp. cinnamomeum var. cinnamomeum var. of ssp. of sp. in subsection ARBOREA
arboreum ssp. cinnamomeum var. roseum var. of ssp. of sp. in subsection ARBOREA
arboreum ssp. cinnamomeum clones
     'Bodnant Pink'
     'Fernhill'
     'Rosenoble'
     'Roseum'
     'Sir Charles Lemon' ?
     'Tony Schilling'
arboreum ssp. cinnamomeum var. cinnamomeum var. of ssp. of sp. in subsection ARBOREA
arboreum ssp. cinnamomeum var. roseum var. of ssp. of sp. in subsection ARBOREA
arboreum ssp. cinnamomeum var. roseum f. album f. of var. of ssp. of sp. in subsection ARBOREA
arboreum ssp. delavayi ssp. of sp. in subsection ARBOREA
arboreum ssp. delavayi clones
     'Margum Castle'
arboreum ssp. delavayi var. albomentosum (tentative) var. of ssp. of sp. in subsection ARBOREA
arboreum ssp. delavayi var. delavayi var. of ssp. of sp. in subsection ARBOREA
arboreum ssp. delavayi var. peramoenum var. of ssp. of sp. in subsection ARBOREA
arboreum ssp. delavayi var. peramoenum var. of ssp. of sp. in subsection ARBOREA
arboreum ssp. delavayi var. piolostylum var. of ssp. of sp. in subsection ARBOREA
arboreum ssp. delavayi var. nilagiricum var. of ssp. of sp. in subsection ARBOREA
arboreum ssp. kingianum syn. R. arboreum ssp. zeylanicum
arboreum ssp. nilagiricum ssp. of sp. in subsection ARBOREA
arboreum ssp. zeylanicum clones
     'Noyo Chief' ?
arboreum ssp. zeylanicum ssp. of sp. in subsection ARBOREA
arboreum ssp. zeylanicum var. kingianum syn. R. arboreum ssp. zeylanicum
arboreum syn. R. arboreum ssp. arboreum
ARBOREUM subseries of ARBOREUM series syn. subsection ARBOREA
archboldianum sp. in subgenus RHODODENDRON section VIREYA subsection SOLENOVIREYA
'Arctic Pearl' clone of white dauricum
arenicolum sp. in subgenus RHODODENDRON section VIREYA subsection ALBOVIREYA
arfakianum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
argenteum syn. R. grande
argipeplum sp. in subsection BARBATA
argyi syn. R. mucronatum var. mucronatum
ARGYROPHYLLA (subsection) subsection of subgenus HYMENANTHES
argyrophyllum sp. in subsection ARGYROPHYLLA
argyrophyllum ssp. argyrophyllum ssp. of sp. in subsection ARGYROPHYLLA
argyrophyllum ssp. hejiangense syn. R. insigne var. hejiangense
argyrophyllum ssp. hypoglaucum clones
     'Heane Wood'
argyrophyllum ssp. hypoglaucum ssp. of sp. in subsection ARGYROPHYLLA
argyrophyllum ssp. nankingense clones
     'Chinese Silver'
argyrophyllum ssp. nankingense ssp. of sp. in subsection ARGYROPHYLLA
argyrophyllum ssp. omeiense ssp. of sp. in subsection ARGYROPHYLLA
argyrophyllum var. cupulare syn. R. argyrophyllum ssp. argyrophyllum
argyrophyllum var. leiandrum syn. R. argyrophyllum ssp. nankingense
ARGYROPHYLLUM subseries of ARBOREUM series syn. subsection ARGYROPHYLLA
aristatum syn. R. barbatum
arizelum clones
     'Brodick'
arizelum sp. in subsection FALCONERA
arizelum ssp. of R. rex ssp. syn. R. arizelum
arizelum var. rubicosum syn. R. arizelum
armitii sp. in subgenus RHODODENDRON section VIREYA subsection SOLENOVIREYA
aromaticum syn. R. anthopogon ssp. anthopogon
artosquameum syn. R. oreotrephes
arunachalense ? sp. in subgenus TSUTSUSI subsection TSUTSUSI
'Ascreavie' A.M. 1978 clone of maddenii ssp. maddenii
'Ashcombe' F.C.C. 1962 clone of veitchianum
x ashitakayamense probable hybrid
ashleyi syn. R. maximum
'Ashleyi' clone of maximum
asmenistum syn. R. sanguineum ssp. sanguineum var. cloiophorum
asmenistum ssp. of R. cloiophorum syn. R. sanguineum ssp. sanguineum var. cloiophorum
assamicum syn. R. formosum
asparagoides syn. R. zolleri
asperrimum sp. in subgenus RHODODENDRON section VIREYA subsection PHAEOVIREYA
asperulum sp. in subgenus RHODODENDRON section VIREYA subsection PSEUDOVIREYA
asperum sp. in subgenus RHODODENDRON section VIREYA subsection PHAEOVIREYA
assamicum syn. R. formosum
asteium syn. R. eudoxum var. mesopolium
asteium ssp. of R. eudoxum syn. R. eudoxum var. mesopolium
asterochnoum var. asterochnoum var. of sp. in subsection FORTUNEA
asterochnoum var. brevipedicellatum var. of sp. in subsection FROTUNEA
astrapiae syn. R. konori var. konori
astrocalyx syn. R. wardii var. wardii
atentsiense syn. R. dendricola
atjehense syn. R. irroratum ssp. kontumense
atlanticum clones
     'Seaboard'
atlanticum sp. in subgenus PENTANTHERA section PENTANTHERA
atlanticum f. confusum syn. R. atlanticum
atlanticum f. luteo-album syn. R. atlanticum
atlanticum f. tomolobum syn. R. atlanticum
atlanticum f. neglectum syn. R. atlanticum
atlanticum var. luteo-album syn. R. atlanticum
atrokermesianum var. of R. meddianum var. of sp. in subsection THOMSONIA
atropunicum sp. in section POGONANTHUM
atropurpureum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
atrorubrum ssp. of R. sanguineum syn. sanguineum ssp. sanguineum var. haemaleum
atrorubrum syn. R. atrovirens
atrovirens sp. in subgenus TSUTSUSI subsection TSUTSUSI
atrovirens var. of R. dauricum syn. R. dauricum
atroviride syn. R. concinnum
'Attar' clone of decorum
aucklandii syn. R. griffithianum
aucklandii var. of R. griffithianum syn. R. griffithianum
aucubaefolium syn. R. stamineum
'Aucubifolium' clone of ponticum
augustinii ssp. augustinii clones
     'Barto Blue'
     'Blue Cloud'
     'Electra'
     'Fair Sky'
     'Lackamas Blue'
     'Marine'
     'Nana'
     'Summer Skies'
     'Tower Court Augustinii'
     'Whalley's Augustinii'
     'Wilson's Augustinii'
augustinii ssp. augustinii ssp. of sp. in subsection TRIFLORA
augustinii ssp. chasmanthum ssp. of sp. in subsection TRIFLORA
augustinii ssp. chasmanthum f. rubrum syn. augustinii ssp. rubrum
augustinii ssp. hardyi ssp. of sp. in subsection TRIFLORA
augustinii ssp. rubrum clones
     'Papillon'
     'Rubrum Davidian'
augustinii ssp. rubrum ssp. of sp. in subsection TRIFLORA
augustinii syn. R. augustinii ssp. augustinii
augustinii var. chasmanthum syn. R. augustinii ssp. chasmanthum
augustinii var. rubrum syn. R. augustinii ssp. rubrum
augustinii var. yui syn. R. augustinii ssp. augustinii
augustinii f. grandiflora syn. R. augustinii ssp. chasmanthum
augustinii f. hardyii syn. R. augustinii ssp. hardyi
augustinii f. subglabra syn. augustinii ssp. chasmanthum
augustissimum ssp. of R. borneese ssp. of sp. in subgenus RHODODENDRON section VIREYA
augustissimum ssp. of R. quadrasianum syn. R. borneense ssp. augustissimum
autantia var. of Azalea speciosa syn. R. calendulaceum
autumnalis var. of Azalea pontica syn. R. luteum
aurantiacum f. of R. calendulaceum syn. R. calendulaceum
aurantiacum var. of R. calendulaceum syn. R. calendulaceum
aurantiacum var. of R. orion syn. R. longiflorum var. longiflorum
aureodorsale ssp. of R. clementinae ssp. of sp. in subsection TALIENSIA
aureolum ssp. of R. citriniflorum syn. R. citriniflorum var. horaeum
aureum syn. R. aureum var. aureum
aureum syn. R. xanthostephanum
aureum f. of japonicum syn. R. molle ssp. japonicum
aureum var. hypopitys var. of R. aureum in subsection PONTICA
aureum var. aureum var. of R. aureum in subsection PONTICA
AURICULATA (subsection [Sleumer]) syn. partly with subsection GRIERSONIANA
AURICULATA (subsection) subsection in subgenus HYMENANTHES
AURICULATUM (series) syn. subsection AURICULATA
auriculatum sp. in subsection AURICULATA
aurigeranum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
auritum sp. in subsection TEPHROPEPLA
australe syn. R. leptothrium
australe ssp. of R. nivale ssp. of sp. in subsection LAPPONICA
austrinum clones
     'Millie Mac'
austrinum sp. in subgenus PENTANTHERA section PENTANTHERA
austrokiusianum syn. R. kiusianum
axillare f. of var. axillare of R. malayanum f. var. of sp. in subgenus RHODODENDRON section VIREYA
axillare var. of R. malayanum var. sp. in subgenus RHODODENDRON section VIREYA
axium ssp. of R. selense syn. selense ssp. selense
axium syn. R. selense ssp. selense
'Ayanohomare' clone of kiusianum
Azalea alabamense syn. R. alabamense
Azalea albiflora syn. R. albiflorum
Azalea albrechtii syn. R. albrechtii
Azalea amagiana syn. R. amagianum
Azalea amoena syn. R. kiusianum 'Amoenum'
Azalea amoena syn. R. obtusum
Azalea arborea syn. R. arborescens
Azalea arborescens syn. R. arborescens
Azalea arborescens var. richardsonii syn. R. arborescens
Azalea atlantica syn. R. atlanticum
Azalea atlantica var. luteo-alba R. atlanticum
Azalea aurantiaca syn. R. calendulaceum
Azalea austrina syn. R. austrinum
Azalea bakeri syn. R. x bakeri syn. R. flammeum x R. canescen
Azalea bicolor syn. R. canescens
Azalea brookeana syn. R. brookeanum var. brookeanum
Azalea calendulacea syn. R. occidentale
Azalea calendulacea syn. R. calendulaceum
Azalea calendulacea var. corcea syn. R. calendulaceum
Azalea calendulacea var. flammea syn. R. flammeum
Azalea californica syn. R. occidentale
Azalea canadensis syn. R. canadense
Azalea candida syn. R. canescens
Azalea canescens syn. R. canescens
Azalea canescens var. candida syn. R. canescens
Azalea citrina syn. R. citrinum var. citrinum
Azalea coccinea syn. R. calendulaceum
Azalea coccinea var.major syn. R. calendulaceum
Azalea crispiflora = R. 'Crispiflorum'
Azalea corcea syn. R. calendulaceum
Azalea cumberlandense syn. R. cumberlandense
Azalea danielsiana = R. 'Danielsianum'
Azalea dianthiflorum = R. 'Dianthiflorum'
Azalea dilatata syn. R. reticulatum
Azalea farrerae syn. R. farrerae
Azalea fastigifolia syn. R. x fastigifolium
Azalea ferruginosa syn. R. lapponicum
Azalea flammea syn. R. calendulaceum
Azalea flava syn. R. luteum
Azalea fragrans syn. R. arborescens
Azalea fragrans syn. R. fragrans
Azalea fulva syn. R. calendulaceum
Azalea furbishii syn R. x furbishii
Azalea glauca syn. R. viscosum
Azalea glauca var. hispida syn. R. viscosum
Azalea hispida syn. R. viscosum
Azalea indica syn. R. simsii
Azalea indica syn. R. indicum
Azalea indica var. calycina = R. 'Omurasaki'
Azalea indica var. lateritia = R. 'Lateritium'
Azalea japonicum syn. R. molle ssp. japonicum
Azalea jasminiflora syn. R. jasminiflorum var. jasminiflorum
Azalea javanica syn. R. javanicum
Azalea kaempferi syn. R. kaempferi
Azalea kiyosumensis syn. R. kiyosumense
Azalea lamponga syn. R. lampongum
Azalea lapponica syn. R. lapponicum
Azalea ledifolia syn. R. mucronatum var. mucronatum
Azalea ledifolia var. phaenicea = R. 'Phoenicea'
Azalea liliiflora syn. R. mucronatum var. mucronatum
Azalea linearfolium syn. R. macrosepalum
Azalea lutea syn. R. calendulaceum
Azalea lutea syn. R. periclymenoides
Azalea lutea syn. R. luteum
Azalea lutea syn. R. canescens
Azalea macrantha = R.'Macranthum'
Azalea macrosepala syn. R. macrosepalum
Azalea makinoi syn. R. makinoi
Azalea makinoi var. muranoana syn. R. makinoi
Azalea malaynan R. malayanum var. malayanum
Azalea mollis syn. R. molle ssp. molle
Azalea mollis var. glabrior syn R. molle ssp. japonicum
Azalea mucronata syn. R. mucronatum var. mucronatum
Azalea multicolor syn. R. multicolor
Azalea myrtifolia syn. R. hongkongense
Azalea neglecta syn. R. atlanticum
Azalea nipponicum syn. R. nipponicum
Azalea nitida syn. R. viscosum
Azalea nudiflora syn. R. roseum syn. R. canescens
Azalea nudiflora syn. R. canescens
Azalea nudiflora syn. R. periclymenoides
Azalea nudiflora var. alba syn. R. alabamense
Azalea nudiflora var. alba syn. R. periclymenoides
Azalea nudiflora var. bicolor syn. R. canescens
Azalea nudiflora var. calycosa syn. R. periclymenoides
Azalea nudiflora var. canescens syn. R. canescens
Azalea nudiflora var. carnea syn. R. periclymenoides
Azalea nudiflora var. ciliata syn. R. occidentale
Azalea nudiflora var. coccinea syn. R. flammeum
Azalea nudiflora var. glandifera syn. R. periclymenoides
Azalea nudiflora var. papilionacea syn. R. periclymenoides
Azalea nudiflora var. partita syn. R. periclymenoides
Azalea nudiflora var. periclymenoides syn. R. periclymenoides
Azalea nudiflora var. polyandra syn. R. periclymenoides
Azalea nudiflora var. rosea syn. R. periclymenoides
Azalea nudiflora var. rosea syn. R. roseum syn. R. canescens
Azalea nudiflora var. rutilans syn. R. periclymenoides
Azalea oblongifolia syn. R. viscosum
Azalea obtusa syn. R. obtusum
Azalea occidentalis syn. R. occidentale
Azalea oldhamii syn. R. oldhamii
Azalea ovata syn. R. ovatum
Azalea parvifolia syn. R. lapponicum
Azalea pennsylvanica syn. R. x pennsylvanicum
Azalea pentaphylla syn. R. pentaphyllum
Azalea periclymena syn. R. periclymenoides
Azalea periclymenoides syn. R. periclymenoides
Azalea periclymenoides var. alba syn. R. periclymenoides
Azalea periclymenoides var. carnea syn. R. periclymenoides
Azalea periclymenoides var. coccinea syn. R. flammeum
Azalea periclymenoides var. papilionacea syn. R. periclymenoides
Azalea periclymenoides var. partia syn. R. periclymenoides
Azalea periclymenoides var. polyandra synl. R. periclymenoides
Azalea periclymenoides var. rutilans syn. R. periclymenoides
Azalea pontica syn. R. luteum
Azalea pontica var. autumnalis syn. R. luteum
Azalea pontica var. sinensis syn. R. molle ssp. japonicum
Azalea pontica calendulacea syn. R. calendulaceum
Azalea prinophylla syn. R. prinophyllum
Azalea prinophylla syn. R. roseum syn. R. canescens
Azalea prunifolia syn. R. prunifolium
Azalea punicea syn. R. x puniceum
Azalea quinquefolia syn. R. quinquefolium
Azalea ramentacea = R. 'Album'
Azalea reticulata syn. R. reticulatum
Azalea retusa syn R. retusum var. retusum
Azalea rhombica syn. R. reticulatum
Azalea rosea syn. R. roseum syn R. canescens
Azalea rosmarinifolia syn. R. mucronatum var. mucronatum
Azalea subseries Canadense syn. in part subgen. PENTANTHERA section SCIADORHODION and subgen. PENTANTHERA section RHODORA
Azalea subseries Luteum syn. subgen. PENTANTHERA section PENTANTHERA
Azalea subseries Nipponicum syn. subgenus PENTANTHERA secion VISCIDULA
Azalea series subseries Obtusum syn. in part section TSUTSUSI
Azalea series subseries Tashiroi syn. in part section TSUTSUSI
Azalea schlippenbachii syn. R. schlippenbachii
Azalea semibarbata syn. R. semibarbatum
Azalea serpyllifolia syn. R. serpyllifolium
Azalea serrulata syn. R. serrulatum syn. R. viscosum
Azalea serrulata var. georgiana syn. R. viscosum
Azalea sinensis syn. R. mollis ssp. japonicum
Azalea sinensis var. glabrior syn. R. mollis ssp. japonicum
Azalea speciosa syn. R. calendulaceum
Azalea speciosa var. aurantia syn. R. calendulaceum
Azalea speciosa var. coccinea syn. R. calendulaceum
Azalea speciosa var. major syn. R. calendulaceum
Azalea squamata syn. R. farrerae
Azalea stenopetala syn. R. stenopetalum
AZALEA subgen. PENTANTHERA syn. genus RHODODENDRON subgen. PENTANTHERA
Azalea sublanceolata syn. R. scabrum
Azalea teysmanni syn. R. javanicum varw. teysmannii
Azalea tomentosa syn. R. viscosum
Azalea tschonoskii syn. R. tschonoskii var. tschonoskii
Azalea tubiflora syn. R. malayanum
Azalea verticillata syn. R. arborescens
Azalea vaseyi syn. R. vaseyi
Azalea viscosa syn. R. arborescens
Azalea viscosa syn. R. viscosum
Azalea viscosa syn. R. serrulatum syn. R. viscosum
Azalea viscosa var. aemulans syn. R. viscosum
Azalea viscosa var. floribunda syn. R. viscosum
Azalea viscosa var. glauca syn. R. viscosum
Azalea viscosa var. hispida syn. R. viscosum
Azalea viscosa var. montana syn. R. viscosum
Azalea viscosa var. nitida syn. R. viscosum
Azalea viscosa var. palustris syn. R. viscosum
Azalea viscosa var. pubescens syn. R. viscosum
Azalea viscosa var. rubescens syn. R. viscosum
Azalea viscosa var. virens syn. R. viscosum
Azalea yodogawa syn. R. yedoense var. yedoense
Azalea x fastigifolia syn. R. flameum x R. canescens
Azalea x furbishii syn. R. cumberlandense x R. arborescens
Azalea x pennsylvanica syn. R. atlanticum x R. periclymenoides
AZALEASTRUM (section) section in subgenus AZALEASTRUM
AZALEASTRUM (subgenus) subgenus in genus RHODODENDRON
Azaleastrum albiflorum syn. R. albiflorum
azaleoides syn. R. ponticum
azureus var. of R. augustinii syn. R. augustinii ssp. augustinii

'Baby Mouse' clone of campylogynum
bachii syn. R. ovatum
baconii sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
baenitzianum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
baeticum syn. R. ponticum
baeticum ssp. of R. ponticum syn. R. ponticum
bagobonum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
'Bagshot Sands' A.M. 1953 clone of R. lutescens
BAILEYA (subsection) subsection in subgenus RHODODENDRON
baileyi only species in subsection BAILEYA
bainbridgeanum sp. in subsection SELENSIA
x bakeri R. flammeum x R. canescens clones
     'Camp's Red'
     'Pink Fire'
     'Scarlet Salute'
x bakeri syn. R. flammeum x R. canescens
balagense sp. in subsection GRANDIA
balfourianum var. aganniphoides var. of sp. in subsection TALIENSIA
balfourianum var. balfourianum var. of sp. in subsection TALIENSIA
'Balsaminaeflorum' clone of indicum
balsaminiflorum syn. R. indicum
banahaoense f. R. quadrasianum syn. R. quadrasianum var. rosmarinifolium
bancanum var. of R. longiflorum var. of sp. in subgenus RHODODENDRON section VIREYA
banghamiorum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
BARBATA (subsection [Sleumer]) syn. partly with subsection GLISCHRA
BARBATA (subsection) subsection in subgenus HYMENANTHES
BARBATUM subseries of BARBATUM series syn. partly with subsection BARBATA
barbatum clones
     'Meteor'
barbatum sp. in subsection BARBATA
barbatum f. imberbe syn. R. x imberbe
barkamense sp. in subsection TALIENSIA
'Baron Lionel' clone of R. degronianum ssp. yakushimanum var. yakushimanum
'Barto Blue' clone of R. augustinii ssp. augustinii
'Barto Rose' clone of R. oreodoxa var. fargesii
'Barto's Favorite' R. clone of fortunei ssp. fortunei
basfordii sp. in subsection MADDENIA
basilicum sp. in subsection FALCONERA
basirotundatum syn. R. javanicum var. teysmannii
basitrichum var. of R. ripleyi var. of sp. in subgenus RHODODENDRON section VIREYA
bantaengense var. of R. lindaueanum var. of sp. in subgenus RHODODENDRON section VIREYA
batangense syn. R. nivale ssp. boreale
x batemannii ? syn. (R. wallichii x R. arboreum)
bathyphyllum sp. in subsection TALIENSIA
bauhiniiflorum (invalid)
bauhiniflorum var. of R. triflorum is invalid
beanianum sp. in subsection NERIIFLORA
beanianum var. compactum syn. R. piercei
beccarii sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
'Beer Sheba' clone of R. cerasinum
beesianum clones
     'Giant Rose'
beesianum sp. in subsection TALIENSIA
beimaense ssp. of R. erythrocalyx syn. R. x erythrocalyx
'Bei-ma-shan' clone of R. hippophaeoides var. hippophaeoides confused with 'Haba Shan'
bellatulum var. of R. eclecteum var. of sp. in subsection THOMSONIA
bellum sp. in subgensu TSUTSUSI section TSUTSUSI
'Benisuzume' clone of R. kiusianum
'Benizakuru' clone of R. kiusianum
'Benizuru' clone of R. kiusianum
'Benmore' F.C.C. 1957 clone of R. montroseanum
'Bennan' clone of R. meddianum var. atrokermesianum
benthamianum syn. R. concinnum
benthamianum var. of R. concinnum syn. R. concinnum
'Bergie' clone of R. ciliatum
bergii syn. R. augustinii var. rubrum
'Berry's Bright Yellow' clone of R. lutescens
'Beryì Taylor' A.M. clone of R. campylogynum
'Beta' clone of R. lanigerum
'Betty' clone of R. kaempferi
'Betty Graham' A.M. 1969 clone of R. anthopogon ssp. anthopogon
'Betty's Purple Russatum' syn. 'Night Editor'
beyerinckianum sp. in subgenus RHODODENDRON section VIREYA subsection PHAEOVIREYA
bahiropatium syn. R. lepidotum
bhutanense sp. in subsection TALIENSIA
bhotanicum syn. R. lindleyi
bicolor syn. R. canescens
bicolor syn. R. simsii var. simsii
bicolor var. of Azalea nudiflora syn. R. canescens
bicorniculatum sp. in subgenus TSUTSUSI subsection TSUTSUSI
bifolium var. of R. reticulatum syn. reticulatum
bijiangense sp. in subsection NERIIFLORA
'Bill Browning' A.M. 1933 clone of R. mallotum
Biltia vaseyi Rhododendron section Rhodora sp. R. vaseyi
x bivelatum ? syn. R. x augustinii ssp. R. chasmanthum
'Blackhills' F.C.C. 1965 clone of R. lacteum
blackii sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
'Blackwater' A.M. 1977 clone of R. spinuliferum
blandfordiaeflorum syn. R. cinnabarinum ssp. cinnabarinum
'Blandfordiaeflorum Group' syn. R. cinnabarinum var. cinnabarinum
blandfordiaeflorum var. of R. cinnabarinum syn. R. cinnabarinum ssp. cinnabarinum
blandinianum unplaced
blandulum syn. R. selense ssp. jucundum
blepharocalyx syn.R. intricatum
blinii syn. R. lutescens
bloembergenii sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
'Blood Red' clone of R. arboreum ssp. R. arboreum
'Blue Cloud' clone of R. augustinii ssp. chasmanthum
'Blue Jay' clone of R. ponticum
'Blue Light' clone of R. brachyanthum ssp. hypolepidotum
blumei sp. subsection GRANDIA, possible syn. R. niveum
bodinieri syn. R. yunnanense or sp. in subsection TRIFLORA
'Bodnant Pink' clone of R. arboreum ssp. cinnamomeum var. roseum
'Bodnant Red' A.M. clone of R. campylogynum
boninense sp. in subgenus TSUTSUSI section TSUTSUSI
bonvalotii sp. in subsection THOMSONIA
BOOTHIA subsection in subgenus RHODODENDRON
boothii sp. in subsection BOOTHIA
BOOTHIA (series) syn. part of subsection TEPHROPEPLA
BOOTHIA (series) syn. in part subsection BOOTHIA
boreale var. of R. dilatatum syn. R. hidakanum
boreale var. of R. sinogrande syn. R. sinogrande
boreale ssp. of R. nivale ssp. of sp. subsection LAPPONICA
borneense sp. in subgenus RHODODENDRON section VIREYA subsection PSEUDOVIREYA
borneense ssp. augustissimum ssp. of sp. in subgenus RHODODENDRON section VIREYA subsection
   PSEUDOVIREYA
borneense ssp. villosum ssp. sp. in subgenus RHODODENDRON section VIREYA subsection PSEUDOVIREYA
borneense var. borneese var. of sp. in subgenus RHODODENDRON section VIREYA subsection
   PSEUDOVIREYA
borneense var. of R. quadrasianum syn. R. borneense var. borneese
brachyandrum syn. R. eclecteum var. eclecteum
brachyandrum var. of R. eclecteum syn. R. eclecteum var. eclecteum
brachyanthum ssp. brachyanthum clones
     'Jaune'
brachyanthum ssp. brachyanthum ssp. of sp. in subsection GLAUCA
brachyanthum ssp. hypolepidotum clones
     'Blue Light'
brachyanthum ssp. hypolepidotum ssp. of sp. in subsection GLAUCA
brachyanthum syn. R. brachyanthum ssp. brachyanthum
brachyanthum var. hypoledidotum syn. brachyanthum ssp. hypolepidotum
BRACYCALYCES (subsection) syn. section BRACHYCALYX
BRACHYCALYX (section) section in subgenus TSUTSUSI
brachycarpum f. normale syn. R. brachycarpum ssp. brachycarpum
brachycarpum ssp. brachycarpum ssp. of sp. in subsection PONTICA
brachycarpum ssp. brachycarpum f. fauriei syn. R. brachycarpum ssp. fauriei f. nematoanum
brachycarpum ssp. brachycarpum f. nematoanum syn. R. brachycarpum ssp. fauriei f. nematoanum
brachycarpum ssp. fauriei ssp. of sp. in subsection PONTICA
brachycarpum ssp. fauriei f. nematoanum f. of ssp. of sp. in subsection PONTICA
brachycarpum ssp. tigerstedtii syn. R. brachycarpum ssp. brachycarpum
brachycarpum syn. R. barchycarpum ssp. brachycarpum
brachycarpum var. lutescens syn R. x nikomontanum
brachycarpum var. nemotaoanum syn. R. brachycarpum ssp. fauriei f. nematoanum
brachycarpum var. roseiflorum syn. R. brachycarpum ssp. fauriei
brachycarpum var. roseum syn. R. brachycarpum ssp. brachycarpum
brachycarpum var. of R. ponticum syn. R. ponticum
brachygynum sp. in subgenus RHODODENDRON section VIREY subsection VIREYA
brachypodarium sp. in subgenus RHODODENDRON section VIREYA subsection SOLENOVIREYA
brachypodum sp. in subsection TRIFLORA
brachysiphon syn. R. maddenii ssp. maddenii
brachystylum syn. R. trichocladum var. trichocladum
brachytrichum var. of R. lateritium syn. R. 'Lateritium'
bracteatum sp. in subsection HELIOLEPIDA
brassii sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
brettii syn. R. longesquamatum
brevicarpum var. of R. ochraceum var. of sp. in subsection MACULIFERA
brevicaudatum sp. in subsection MICRANTHA
breviforme var. of R. cinnabarinum ssp. cinnabarinum var. of ssp. of sp. in subsection
   CINNABARINA
brevinerve sp. in subsection IRRORATA
brevipedicellatum var. of asterochnoum var. of sp. in subsection FORTUNEA
breviperulatum sp. in subgenus TSUTSUSI subsection TSUTSUSI
brevipes sp. in subgenus RHODODENDRON section VIREY subsection VIREYA
brevipetiolatum sp. in subsection ARGYROPHYLLA
brevistylum syn. R. heliolepis var. brevistylum
brevistylum var. of R. heliolepis var. of sp. in subsection HELIOLEPIDA
brevitubum syn. R. maddenii ssp. maddenii
brevitubum syn. R. crassifolium
breynii = R. 'Breynii'
'Brodick' A.M. 1963 clone of R. rex ssp. arizelum
'Brookings Deep Pink' clone of R. macrophyllum
brookeanum ssp. brookeanum ssp. of sp. in subgenus RHODODENDRON section VIREYA subsection
   VIREYA
brookeanum ssp. brookeanum var. brookeanum var. of ssp. of sp. in subgenus RHODODENDRON
   section VIREYA subsection VIREYA
brookeanum ssp. brookeanum var. cladotrichum var. of ssp. of sp. in subgenus RHODODENDRON
   section VIREYA subsection VIREYA
brookeanum ssp. brookeanum var. extraneum var. of ssp. of sp. in subgenus RHODODENDRON
   section VIREYA subsection VIREYA
brookeanum ssp. brookeanum var. gracile syn. R. brookeanum ssp. gracile
brookeanum ssp. brookeaanum var. kinabaluense var. of ssp. sp. in subgenus RHODODENDRON
   section VIREYA subsection VIREYA
brookeanum ssp. brookeanum var. moultonii var. of ssp. of sp. in subgenus RHODODENDRON
   section VIREYA subsection VIREYA
brookeanum ssp. cockburnii ssp. of sp. in subgenus RHODODENDRON section VIREYA
   subsection VIREYA
brookeanum ssp. gracile ssp. of sp. in subgenus RHODODENDRON section VIREYA
   subsection VIREYA
brookeanum ssp. of R. javanicum syn. R. brookeanum var. brookeanum
bookeanum syn. R. retivenium
brunneifolium syn. R. eudoxum var. brunneifolium
brunneifolium ssp. of R. eudoxum syn. R. eudoxum var. brunneifolium
brunneifolium var. of R. eudoxum var. of sp. in subsection NERIIFLORA
bryophilum sp. in subgenus RHODODENDRON section VIREYA subsection PHAEOVIREYA
'Budget Farthing' A.M. 1969 clone of R. oreodoxa var. fargesii
buergeri syn. R. obtusum
bullatum syn. R. edgeworthii
bullifolium sp. in subgenus RHODODENDRON section VIREYA subsection PHAEOVIREYA
bulu sp. in subsection LAPPONICA
bureavii sp. in subsection TALIENSIA
bureavioides syn. R. faberi
burjaticum sp. in subsection LAPPONICA
burmanicum clones
     'Elizabeth David'
burmanicum sp. in subsection MADDENIA
burnannii syn. R. mucronatum var. mucronatum
burrifolium syn.R. diphrocalyx
burtii sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
buruense sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
'Butcher Wood clone of R. tephropeplum
'Butheana' clone of R. mucronatum (possible hybrid)
butyricum syn. R. chrysodoron
buxifolium sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
buxifolium var. robustum syn. R. buxifolium
buxoides sp. in subgenus RHODODENDRON section VIREYA subsection PSEUDOVIREYA

'Caarse' or 'Carse' clone of R. irroratum ssp. irroratum
'Caerhay's Pink' clone of R. davidsonianum
caeruleo-glaucum syn. R. campylogynum
caeruleum syn. R. rigidum
caesium sp. in subsection TRICHOCLADA
caespitosum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
caespitulum syn. R. myrsinifolium
calceolariodes syn. R. macgregoriae var. macgregoriae
calcicolum syn. R. cuneatum
calciphilum syn. R. calostrotum ssp. riparium
calciphyllum var. of calostrotum syn. R. calostrotum ssp. riparium
calendulaceum f. croceum syn. R. calendulaceum
calendulaceum clones
     'Colossus'
     'Smoky Mountaineer'
calendulaceum sp. in section PENTANTHERA subsection PENANTHERA
calendulaceum f. aurantiacum syn. R. calendulaceum
calendulaceum var. aurantiacum syn. R. calendulaceum
californicum syn. R. macrophyllum
caliginis sp. in subgenus RHODODENDRON section VIREYA subsection PHAEOVIREYA
calleryi syn. R. simsii var. simsii
callichilioides syn. R. wentianum
callichilioides var. minor syn. R. wentianum
callimorphum var. callimorphum clones
     'Second Attempt'
callimorphum var. callimorphum var. of sp. in subsection CAMPYLOCARPA
callimorphum var. myiagrum var. of sp. in subsection CAMPYLOCARPA
calococdon syn. R. pauciflorum
calocodon var. R. pauciflorum var. of sp. in subgenus RHODODENDRON section VIREYA
calophyllum syn. R. maddenii ssp. maddenii
calophytum ssp. jinfuense ssp. of sp. in subsection FORTUNEA
calophytum syn. R. calophytum var. calophytum
calophytum var. calophytum var. of sp. in subsection FORTUNEA
calophytum var. openshawianum var. of sp. in subsection FORTUNEA
calophytum var. pauciflorum var. of sp. in subsection FORTUNEA
calosanthes sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
calostrotum var. calciphilum syn. R. calostrotum ssp. riparium
calostrotum ssp. calostrotum clones
     'Gigha'
calostrotum ssp. calostrotum ssp. of sp. in subsection SALUENENSIA
calostrotum ssp. keleticum ssp. of sp. in subsection SALUENENSIA
calostrotum ssp. ripariodes ssp. of sp. in subsection SALUENENSIA
calostrotum ssp. riparium ssp. of sp. in subsection SALUENENSIA
calostrotum syn. R. calostrotum ssp. calostrotum
calostrotum var. calciphyllum syn. R. calostrotum ssp. riparium
calostrotum var. riparioides syn. R. calostrotum ssp. riparioides
caloxanthum syn. R. campylocarpum ssp. caloxanthum
caloxanthum ssp. of R. campylocarpum ssp. of sp. in subsection CAMPYLOCARPA
calvescens syn. R. calvescens var. calvescens
calvescens var. calvescens var. of sp. in subsection SELENSIA
calvescens var. duseimatum var. of sp. in subsection SELENSIA
calycinum syn. R. 'Omurasaki'
calycinum var. of R. haematodes syn. R. haematodes ssp. haematodes
CAMELLIIFLORUM (series) syn. subsection CAMELLIIFLORA
CAMELLIIFLORA subsection in subgenus RHODODENDRON
camelliiflorum only species in subsection CAMELLIIFLORA
CAMPANULATA (subsection [Sleumer]) syn. partly with subsection LANATA
CAMPANULATA (subsection) subsection in subgenus HYMENANTHES
CAMPANULATUM (series) syn. partly with subsection LANATA
CAMPANULATUM (series) syn. partly with subsection CAMPANULATA
campanulatum ssp. aeruginosum ssp. of sp. in subsection CAMPANULATA
campanulatum ssp. campanulatum clones
     'Rolanä Cooper'
     'Waxen Bell'
campanulatum ssp. campanulatum ssp. of sp. in subsection CAMPANULATA
campanulatum syn. R. campanulatum ssp. campanulatum
campanulatum var. aeruginosum syn R. campanulatum ssp. aeruginosum
campanulatum var. campbellii syn. R. wallichii x arboreum
campbelliae syn. R. arboreum ssp. cinnamomeum var. cinnamomeum
'Campbelliae Group syn. R. arboreum ssp. arboreum
campbelliae ssp. of R. arboreum syn. R. arboreum ssp. cinnamomeum var. cinnamomeum
campbellii var. of R. campanulatum ? syn.(R. wallichii x R. arboreum)
'Campbell's Strain' clone of R. wardii var. wardii
'Camp's Red' clone of R. x bakeri
CAMPYLOCARPA (subsection) subsection in subgenus HYMENANTHES
campylocarpum ssp. caloxanthum ssp. of sp. in subsection CAMPYLOCARPA
campylocarpum ssp. campylocarpum ssp. of sp. in subsection CAMPYLOCARPA
campylocarpum ssp. telopeum syn. R. campylocarpum ssp. caloxanthum
campylocarpum syn. R. campylocarpum ssp.campylocarpum
CAMPYLOCARPUM subseries of THOMSONII series syn. subsection CAMPYLOCARPA
CAMPYLOGYNA (subsection) subsection in subgenus RHODODENDRON
CAMPYLOGYNUM (series) syn. subsection CAMPYLOGYNA
campylogynum clones
     'Baby Mouse'
     'Beryl Taylor'
     'Bodnant Red'
     'Crushed Strawberry'
     'Jade'
     'Kim'
     'Leucanthum'
     'Little Amy'
     'Patricia'
     'Plum Warner'
     'Thimble'
campylogynum only species in subsection CAMPYLOGYNA
campylogynum var. celsum syn. R. campylogynum
campylogynum var.charopoeum syn. R. campylogynum
campylogynum var. cremastum syn. R. campylogynum
campylogynum var. eupodum syn. R. campylogynum
campylogynum var. leucanthum cultivated variant of campylogynum
campylogynum var. myrtilloides syn. R. campylogynum
CAMTSCHATICUM (series) syn. with subgenus THERORHODION
camtschaticum ssp. camtschaticum ssp. of sp. in subgenus THERORHODION
camtschaticum ssp. glandulosum ssp. of sp. in subgenus THERORHODION
camtschaticus syn. R. camtschaticum
CANADENSA subseries of series AZALEA syn. partly for susbgen. PENTANTHERA section RHODORA
CANADENSA subseries of series AZALEA syn. partly with section SCIADORHODION
canadense sp. in subgen. PENANTHERA section RHODORA
canadense f. albiflorum syn. R. canadense
canadense f. album syn. R. canadense
canadense f. viridifolium syn. R. canadense
x candelabrum syn. (R. thomsonii x ? R. campylocarpum)
candelabrum ssp. of R. thomsonii see candelabrum
candelabrum var. thomsonii see candelabrum
candidapiculatum syn. R. pusillum
CANDIDASTRUM (section[Sleumer]) syn. with subgenus CANDIDASTRUM
CANDIDASTRUM (subgenus) subgenus in genus RHODODENDRON
candida var. of Azalea canescens syn. R. canescens
candidum syn. R. canescens
candidum var. of R. canescens syn. R. canescens
canescens f. subglabrum syn. R. canescens
canescens sp. in subgenus PENTANTHERA section PENTANTHERA
canescens syn. R. prinophyllum
canescens var. candidum syn. R. canescens
cantabile syn. R. russatum
'Canton Consul' A.M. 1957 clone of R. hanceanum
capellae sp. in subgenus RHODODENDRON section VIREYA unplaced
capitatum syn. R. fastigiatum
capitatum sp. in subsection LAPPONICA
cardatum syn. R. souliei
cardiobasis syn. R. orbiculare ssp. cardiobasis
cardiobasis ssp. of R. orbiculare ssp. of sp. in subsection FORTUNEA
cardoeoides syn. R. oreotrephes
'Carmelita' clone of R. forrestii ssp. papillatum
carnea var. of Azalea nudiflora syn. R. periclymenoides
carnea var. of Azalea periclymenoides syn. R. periclymenoides
carneum sp. in subsection MADDENIA
CAROLINIANA (subsection) subsection in subgenus RHODODENDRON
'Carolinianum Group' syn. R. minus
carolinianum syn. R. minus var. minus
carrii sp. in subgenus RHODODENDRON section VIREYA subsection SOLENOVIREYA
carringtoniae syn. R. herzogii
carringtoniae sp. in subgenus RHODODENDRON section VIREYA subsection SOLENOVIREYA
carringtoniae var. maius syn. R. maius
'Carse' or 'Caarse' clone of R. irroratum ssp. irroratum
carstensense sp. in subgenus RHODODENDRON section VIREYA subsection SOLENOVIREYA
x cartonianum syn. R. catawbiense x periclymenoides
caryophyllum syn. R. rubropilosum
catacosmum sp. in subsection NERIIFLORA
'Catalgla' clone of white R. catawbiense
catanduanense syn. R. nortoniae
'Catanea' clone of white R. catawbiense
catapastum syn. R. rubiginosum var. rubiginosum
'Catawbiense Album' ? clone of R. catawbiense
'Catawbiense Boursault' ? clone of R. catawbiense
'Catawbiense Grandiflorum' ? clone of R. catawbiense
catawbiense clones
     'Catalgla'
     'Catanea'
     'Catawbiense Album' ?
     'Catawbiense Boursault' ?
     'Catawbiense Grandiflorum' ?
     'La Bar's White'
     'Powell Glass'
     'Virgin'
catawbiense sp. in subsection PONTICA
catesbaeum R. ponticum x
caucaseum syn. R. caucasicum
caucasicum clones
     'Cunningham's Sulfur'
     'Original'
     'The Bride'
     'White's Cunningham's Sulfur'
caucasicum sp. in subsection PONTICA
cavaleriei sp. in section CHONIASTRUM
calvaleriei var. chaffanjonii syn. R. stamineum var. stamineum
x carvoni = hybrid
'Cecil Nice' A.M. 1971 clone of R. pocophorum var. pocophorum
celebicum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
'Celsum Group' syn. R. campylogynum
celsum var. of R. campylogynum syn. R. campylogynum
cephalanthoides syn. R. primuliflorum
cephalanthoides var. of R. primuliflorum syn. R. primuliflorum
CEPHALANTHUM (series) syn. with section POGONANTHUM
cephalanthum syn. R. cephalanthum ssp. cephalanthum
cephalanthum ssp. cephalanthum clones
     'Winifred Murray'
cephalanthum ssp. cephalanthum ssp. of sp. in section POGONANTHUM
cephalanthum ssp. platyphyllum ssp. of sp. in section POGONANTHUM
cephalanthum var. crebreflorum syn. R. cephalanthum ssp. cephalanthum
cephalanthum var. platyphyllum syn. R. cephalanthum ssp. platyphylllum
cephalanthum var. nmaiense syn. R. cephalanthum ssp. cephalanthum
ceraceum syn. R. lukiangense
'Ceramic' clone of R. wardii var. wardii
cerasiflorum syn. R. campylogynum
CERASINUM subseries of THOMSONII series syn. partly subsection THOMSONIA
cerasinum clones
     'Beer Sheba'
     'Cherry Brandy'
     'Coals of Fire'
     'Herbert Mitchell'
cerasinum sp. in subsection THOMSONIA
cerinum syn. R. sulfureum
cernuum sp. in subgenus RHODODENDRON section VIREYA subsection ALBOVIREYA
cerochitum syn. R. tanastylum var. tanastylum
chaetomallum syn. R. haematodes ssp. chaetomallum
chaetomallum ssp. of R. haematodes ssp. of sp. in subsection NERIIFLORA
chaetomallum var. chamaephytum syn. ? (R. forrestii x R. haematodes)
chaetomallum var. glaucescens syn. R. haematodes ssp. chaetomallum
chaetomallum var. hemigymnum syn. R. x hemigymnum
chaetomallum var. xanthanthum syn. R. x xanthanthum
chaffanjonii syn. R. stamineum
chaffanjonii var. of calvaleriei syn. R. stamineum var. stamineum
chalarocladum ssp. of R. selense syn. selense ssp. selense
chalarocladum syn. R. selense ssp. selense
'Chamadoron' clone of R. chamaethomsonii var. chamaethomsonii
Chamaecistus kamtschaticus syn. R. camtschaticum
chamaecystys syn. Rhodothamus chamaecistus
chamaedoron var. of R. chamaethomsonii var. of sp. in subsection NERIIFLORA
chamaepitys sp. in subgenus RHODODENDRON section VIREYA subsection SOLENOVIREYA
chamaethomsonii syn. R. chamaethomsonii var. chamaethomsonii
chamaethomsonii var. chamaedoron var. of sp. in subsection NERIIFLORA
chamaethomsonii var. chamaethauma var. of sp. in subsection NERIIFLORA
chamaethomsonii var. chamaethomsoni var. of sp. in subsection NERIIFLORA
chamaedoron var. of R. chamaethomsonii var. of sp. in subsection NERIIFLORA
chamaethauma var. of R. chamaethomsonii var. of sp. in subsection NERIIFLORA
chamaethomsonii var. chamaethomsonii clones
     'Chamadoron'
chamaethomsonii var. chamaethomsonii var. of sp. in subsection NERIIFLORA
chamaetortum syn. R. cephalanthum ssp. cephalanthum
x chamaezelum syn. (R. tapetiforme x R. rupicola var. chryseum)
chameunum ssp. of R. saluenense ssp. of sp. in subsection SALUENENSIA
chameunum syn. R. saluenense ssp. chameunum
chamaezelum sp. in subsection LAPPONICA
championae syn. championae var. championae
championae var. championae var. of sp. in section CHONIASTRUM
championae var. ovatifolium var. of sp. in section CHONIASTRUM
changii sp. in subsection MADDENIA
changii var. of R. valentinianum syn. R. changii
chaoanense sp. in subgenus TSUTSUSI section TSUTSUSI
chapaense syn. R. maddenii ssp. crassum
'Chapel Wood' A.M. 1961, F.C.C. 1967 clone of R. lanigerum
chapmanii syn. R. minus var. chapmanii
chapmanii var. of R. minus var. of sp. in subsection CAROLINIANA
x charadzeae syn. R. smirnowii x R. ungernii
charianthum syn. R. davidsonianum
charidotes syn. R. saluenense ssp. chameunum
charitopes syn. R. charitopes ssp. charitopes
charitopes ssp. charitopes clones
     'Parkside'
charitopes ssp. charitopes ssp. of sp. in subsection GLAUCA
charitopes ssp. tsangpoense clones
     'Cowtye'
charitopes ssp. tsangpoense ssp. of sp. in subsection GLAUCA
charitostreptum syn. R. brachyanthum ssp. hypolepidotum
charopoeum syn. R. campylogynum
'Charopoeum Group' syn. R. campylogynum
charopoeum var. of R. campylogynum syn. R. campylogynum
chartophyllum syn. R. yunnanense
chartophyllum f. praecox syn R. yunnanense
chasmanthoides syn. R. augustinii ssp. chasmanthum
chasmanthum syn. R. augustinii ssp. chasmanthum
chasmanthum ssp. of R. augustinii ssp. of sp. in subsection TRIFLORA
chasmanthum var. of R. augustinii syn. R. augustinii ssp. chasmanthum
chawchiense syn. R. anthosphaerum
cheilanthum syn. R. cuneatum
'Cheiranthifolium' clone of ponticum
chejuense var. of R. mucronulatum var. of sp. in subsection RHODORASTRA
'Chelsea Chimes' A.M. 1979 clone of R. coryanum
chengianum syn. R. hemsleyanum
chengshienianum sp. in subection TRIFLORA
chevalieri sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
chiengshienianum syn. ambiguum
'Cherry Brandy' A.M. 1938 clone of R. cerasinum
'Cherry Tip' A.M. 1953 clone of R. rex ssp. fictolacteum
'Chidori' clone of white R. kiusianum
'Chief Paulina' clone of R. concinnum
chienianum syn. R. longipes var. chienianum
chienianum var. of R. longipes var. of sp. in subsection ARGYROPHYLLA
chihsinianum sp. in subsection AURICULATA
'Chinese Silver' clone of R. argyrophyllum ssp. nankingense
chionanthum sp. in subsection NERIIFLORA
chionophyllum syn. R. argyrophyllum ssp. argyrophyllum
chlanidotum syn. R. citriniflorum var. citriniflorum
chloranthum syn. R. mekongense var. melinanthum
x chlorops ? syn. (R. wardii x R. vernicosum)
x chlorops clone 'Lackamas Cream'
chlorops var. of R. oreites var. sp. in section VIREYA subsection PSEUDOVIREYA
CHONIASTRUM (section) section in subgenus AZALEASTRUM
christianae sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
christii sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
christi syn R. christii
christi var. loniceroides syn. R. christii
chrysanthemum syn. R. temenium var. gilvum
chrysanthum syn. R. aureum var. aureum
chrysanthum var. nikomontanum syn. R. x nikomontanum
chrysanthum ssp. of R. temenium syn. R. temenium var. gilvum
chryseum syn. rupicola var. chryseum
chryseum var. of R. rupicola var. of sp. in subsection LAPPONICA
chrysocalyx sp. in subgenus TSUTSUSI section TSUTSUSI
chrysodoron sp. in subsection BOOTHIA
chrysolepis ? sp. in section Rhododendron known inadequately
chunienii sp. in subsection MADDENIA
chunii sp. in subgenus TSUTSUSI section TSUTSUSI
'Church Lane' clone of degronianum ssp. yakushimanum var. yakushimnum
ciliata var. of Azalea nudiflora syn. R. occidentale
ciliato-pedunculatum syn. R. henryi var. henryi
ciliatum clones
     'Bergie'
ciliatum sp. in subsection MADDENIA
ciliatum f. of R. mucronulatum f. of sp. in subsection RHODORASTRA
ciliatum var. of R. mucronulatum syn. R. mucronulatum
ciliicalyx clones
     'Walter Maynard'
ciliicalyx sp. in subsection MADDENIA
ciliilobum sp. in subgenus RHODODENDRON section VIREYA subsection PSEUDOVIREYA
ciliipes sp. in subsection MADDENIA
'Ciliocale' unknown c.w. Delavay
cinchoniflorum sp. in subgenus RHODODENDRON section VIREYA subsection SIPHONOVIREYA
cinerascens sp. in subgenus RHODODENDRON section VIREYA subsection SOLENOVIREYA
cinereoserratum syn. R. farrerae
cinereum syn. R. cuneatum
CINNABARINA (subsection) subsection in subgenus RHODODENDRON
cinnabarinum syn. R. cinnabarinum ssp. cinnabarinum
CINNABARINUM Series syn. subsection CINNABARINA
cinnabarinum ssp. cinnabarinum clones
     'Aestivale'
     'Crarae Crimson'
     'Cuprea'
     'Darjeeling'
     'Magnificum'
     'Mount Everest'
     'Nepal'
     'Postling'
     'Vin Rose'
cinnabarinum ssp. cinnabarinum ssp. of in subsection CINNABARINA
cinnabarinum ssp. tamaense clones
     'Triangle'
cinnabarinum ssp. tamaense ssp. of sp. in subsection CINNABARINA
cinnabarinum ssp. xanthocodon clones
     'Copper'
cinnabarinum ssp. xanthocodon ssp. of sp. in subsection CINNABARINA
cinnabarinum var. blandforiiflorum syn. R. cinnabarinum ssp. cinnabarinum
cinnabarinum ssp. cinnabarinum var. breviforme var. of ssp. of sp. in subsection CINNABARINA
cinnabarinum var. pallidum syn. R. cinnabarinum ssp. xanthocodon
cinnabarinum var. purpurellum syn. R. cinnabarinum ssp. xanthocodon
cinnabarinum var. roylei syn. R. cinnabarinum ssp. cinnabarinum
cinnabarinum var. aestivale syn. R. cinnabarinum ssp. cinnabarinum
cinnamomeum syn. R. arboreum ssp. cinnamomeum var. cinnamomeum
cinnamomeum ssp. of R. arboreum ssp. of sp. in subsection ARBOREA
cinnamomeum var. of R. cinnamomeum ssp. of arboreum var. of ssp. of sp. in subsection ARBOREUM
circinnatum sp. in subsection LANATA
cistiflorum syn. Rhodothamus chamaecistus
citriniflorum ssp. aureolum syn. R. citriniflorum var. horaeum
citriniflorum ssp. horaeum syn. R. citriniflorum var. horaeum
citriniflorum ssp. rubens syn. R. citriniflorum var. horaeum
citriniflorum syn. R. citriniflorum var. citriniflorum
citriniflorum var. horaeum var. of sp. in subsection NERIIFLORA
citriniflorum var. citriniflorum var. of sp. in subsection NERIIFLORA
citrinum syn. R. citrinum var. discoloratum
citrinum var. citrinum var. of sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
citrinum var. discoloratum var. of sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
citrinum f. albiflorum syn. citrinum var. citrinum
citrinum unplaced
Cladothamnus campanulatus syn. R. albiflorum
cladotrichum var. of ssp. of R. brookeanum ssp. brookeanum var. of ssp. of sp. in
   subgenus RHODODENDRON section VIREYA
clementinae ssp. aureodorsale ssp. of sp. in subsection TALIENSIA
clementinae ssp. clementinae ssp. of sp. in subsection TALIENSIA
clementis syn R. javanicum ssp. schadenbergii
clivicolum syn. R. primuliflorum
cloiophorum syn. R. sanguineum ssp. sanguineum var. cloiophorum
cloiophorum ssp. of sanguineum syn. R. sanguineum ssp. sanguineum var. cloiophorum
cloiophorum ssp. mannophorum syn. R. sanguineum ssp. sanguineum var. didymoides
cloiophorum ssp. roseotinctum syn. R. sanguineum ssp. sanguineum var. didymoides
cloiophorum var. of R. sanguineum ssp. sanguineum var. of ssp. of sp. in subsection NERIIFLORA
'Clyne Castle' clone of R. niveum
'Coals of Fire' clone of R. cerasinum
coccinea var. of Azalea nudiflora syn. R. flammeum
coccinea var. of Azallea periclymenoides syn. R. flammeum
coccinea var. of Azalea speciosa syn. R. calendulaceum
coccineum var. of R. nudiflorum syn. R. flammeum
'Cocinea' clone of R. ferrugineum
coccinopeplum syn. R. roxieanum var. cucullatum
cockburnii ssp. of sp. R. brookeanum in subgenus RHODODENDRON section VIREYA
cockburnii ssp. of R. javanicum syn. R. brookeanum ssp. cockburnii
codonanthum sp. in subsection TALIENSIA
coelicum sp. in subsection NERIIFLORA
coeloneuron sp. in subsection TALIENSIA
coelorum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
coerulescens froma of R. viscosum syn. R. viscosum
coenenii syn. R. culminicolum var. nubicola
collettianum sp. in section POGONANTHUM
colletum syn. R. beesianum
'Collingwood Ingram' F.C.C. clone of R. trichostomum
colobodes syn. R. saluenense ssp. chameunum
'Colossus' clone of R. calendulaceum
columbianum sp. in subsecton LEDUM
comisteum sp. in subsection TALIENSIA
commodum syn. R. sulfureum
commonae sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
commutatum syn. R. longiflorum var. longiflorum
compactum f. beanianum syn. R. piercei
compactum syn. R. polycladum
compactum var. of R. beanianum syn. R. piercei
comparabile sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
complexum sp. in subsection R. LAPPONICA
comptum var. comptum var. of sp. in subgenus RHODODENDRON section VIREYA subsection ALBOVIREYA
comptum var. trichodes var. of sp. in subgenus RHODODENDRON section VIREYA subsection ALBOVIREYA
concatenans syn. R. cinnabarinum ssp. xanthocodon
'Concatenans Group' syn. R. cinnabarinum ssp. R. xanthocodon
concinnoides sp. in subsection MONANTHA
concinnum clones
     'Chief Paulina'
     'Fake'
     'James' Purple'
     'Purple Lustre'
concinnum sp. in subsection TRIFLORA
concinnum var. benthamianum syn. R. conncinum
concinnum var. pseudoyanthinum syn. R. concinnum
confertissimum syn. R. lapponicum
confusum f. of R. atlanticum syn. R. atlanticum
coniferum syn. R. correoides
consanguineum ssp. of R. sanguineum syn. R. sanguineum ssp. sanguineum var. didymoides
'Convexum' clone of R. degronianum ssp. yakushimanun var. yakushimanum
convexum syn. R. culminicolum var. culminicolum
'Cook's Russatum' clone of R. russatum
cookeanum syn. R. sikangense var. sikangense
coombense syn. R. concinnum
cooperi syn. R. camelliiflorum
copelandii syn. R. jasminiflorum var. copelandii
copelandii var. of R. jasminiflorum var. of sp. in subgenus RHODODENDRON section VIREYA
'Copper' A.M. 1950 clone of R. cinnabarinum ssp. xanthocodon
'Copse Belt' clone of R. lepidotum
cordatum syn. souliei
cordatum var. of R. decorum ssp. decorum var. of ssp. of sp. in subsection FORTUNEA
cordifolium--unplaced
coreanum syn. R. yedoense var. poukhanense
coriaceum clones
     'Morocco'
coriaceum sp. in subsection FALCONERA
x coriifolium syn. R. buxifolium x rugosum
coriifolium syn. x coriifolium
coriifolium var. of R. rugosum syn. R. x coriifolum
'Cornell Pink' clone of R. mucronulatum
cornu-bovis sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
coronarium syn. R. luteum
correoides sp. in subgenus RHODODENDRON section VIREYA subsection ALBOVIREYA
corruscum syn. R. wrayi
'Corsock' clone of R. phaeochrysum var. phaeochrysum
coryanum clones
     'Chelsea Chimes'
coryanum sp. in subsection ARGYROPHYLLA
coryi syn R. viscosum
coryphaeum syn. R. praestans
cosmetum syn. R. saluenense ssp. chameunum
costulatum syn. R. lutescens
cowanianum sp. in subsection LEPIDOTA
'Cowtye' A.M. 1972 clone of R. charitopes ssp. tsangpoense
'Cox Apricot Racemosum' clone of R. racemosum
coxianum sp. in subsection MADDENIA
'Crarae Crimson' clone of R. cinnabarinum ssp. cinnabarinum
crassifolium sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
crassifolium var. of seniavinii var. of sp. in subgenus TSUTSUSI section TSUTSUSI
crassimedium syn. R. polyraphidoideum var. polyraphidoideum
crassinervium syn. R. crassifolium
crassum syn. R. maddenii ssp. crassum
crassum ssp. of R. maddenii ssp. of sp. in subsection MADDENIA
'Crater's Edge' clone of R. mucronulatum
crebreflorum syn. R. cephalanthum ssp. cephalanthum
crebreflorum var. of cephalanthum syn. R. cephalanthum ssp. cephalanthum
'Crebreflorum Group' syn. R. cephalanthum ssp. cephalanthum
crebreflorum var. of R. cephalanthum syn. R. cephalanthum ssp. cephalanthum
cremastum syn. R. campylogynum
'Cremastum Group' syn. R. campylogynum
cremastum var. of R. campylogynum syn. R. campylogynum
cremnastes syn. R. lepidotum
cremnophilum syn. R. primuliflorum
crenatum syn. R. racemosum
crenulatum sp. in subsection MADDENIA
'Crescent City Double' clone of R. occidentale
'Crescent City Gold' clone of R. occidentale
cretaceum sp. in subgenus TSUTSUSI subsection TSUTSUSI
crinigerum syn. R. crinigerum var. crinigerum
crinigerum var. euadenium var. of sp. in subsection GLISCHRA
crinigerum var. of R. crinigerum var. of sp. in subsection GLISCHRA
crispiflorum = R. 'Crispiflorum'
crocea var. of Azalea calendulacea syn. R. calendulaecum
croceum f. of R. calendulaceum syn. R. calendulaceum
croceum syn. R. wardii var. wardii
'Crown Equerry' clone of R. niveum
'Cruachan' F.C.C. 1958 clone of R. temenium var. gilvum
cruentum syn. R. bureavii
cruttwellii sp. in subgenus RHODODENDRON section VIREYA subsection SOLENOVIREYA
cryptogonium var. of R. ripleyi var. of sp. in subgenus RHODODENDRON section VIREYA
cryptonerve var. R. naamkwanense var. of sp. in subgenus TSUTSUSI section TSUTSUSI
'Crushed Strawberry' clone of R. campylogynum
cubitii syn. R. veitchianum
'Cubitii Group' syn. R. veitchianum
cucullatum syn. R. roxieanum var. cucullatum
cucullatum var. of R. roxieanum var. of sp. in subsection TALIENSIA
cuffeanum sp. in subsection MADDENIA
culminicolum syn. R. culminicolum var. culminicolum
culminicolum var. angiense var. of sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
culminicolum var. culminicolum var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection VIREYA
culminicolum var. nubicola var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection VIREYA
cumberlandense sp. in subgenus PENTANTHERA section PENANTHERA
cuneatum sp. in subsection LAPPONICA
cuneifolium syn. R. quadrasianum var rosmarinifolium
cuneifolium var. cuneifolium var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection PSEUDOVIREYA
cuneifolium var. microcarpum var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection PSEUDOVIREYA
cuneifolium var. of R. quadrasianum syn. R. cuneifolium var. cuneifolium
cuneifoium var. subspathulatum syn. R. borneense ssp. villosum
cuneifolium var. subspathulatum syn. R. bogobonum
cuneifolium syn. R. borneense
x cunninghamii = R. 'Cunninghamii'
'Cunningham's Sulphur' clone of R. caucasicum
'Cuprea' A.M. 1954 clone of R. cinnabarinum ssp. cinnabarinum
cupresens syn. R. phaeochrysum var. R. phaeochrysum
curranii syn. R. whiteheadii
curtisii syn. R. milticolor
cupulare var. of R. argyrophyllum syn. R. argyrophyllum ssp. argyrophyllum
curviflorum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
curvistylum syn. R. charitopes ssp. tsangpoense
'Curvistylum Group' syn. R. charitopes ssp. tsangpoense
curvistylum var. of R. tsangpoense syn. R. tsangpoense ssp. tsangpoense
cuspidellum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
cuthbertii syn. R. minus var. minus
cyanocarpum var. of R. thomsonii syn. R. cyanocarpum
cyanocarpum sp. in subsection THOMSONIA
cyanocarpum var. eriphyllum syn. R. cyanocarpum
cyatheicolum syn. R. spondylophyllum
cyclium syn. R. callimorphum var. callimorphum
cyclopense var. of R. wrightianum var. of sp. in subgenus RHODODENDRON section VIREYA
cyclopicum var. of R. lindaueanum syn. linaueanum var. linaueanum
cymbomorphum syn. R. x erythrocalyx
'Cyril Berkeley' clone of R. forrestii ssp. papillatum
cyrtophyllum sp. in subgenus RHODODENDRON section VIREYA

dabanshanense syn. R. przewalskii
dahuricum syn. R. dauricum
daiyuenshanicum syn. daiyunicum
daiyunicum sp. in subgenus TSUTSUSI section BRACHYCALYX
dalhousiae syn. R. dalhousiae var. dalhousiae
dalhousiae var. dalhousiae clones
     'Frank Ludlow'
     'Tom Spring Smythe'
dalhousiae var. dalhousiae var. of sp. in subsection MADDENIA
dalhousiae var. rhabdotum var. of sp. in subsection MADDENIA
'Dalkeith' clone of R. uniflorum var. uniflorum
'Dalriada' clone of R. degronianum ssp. degronianum
damascenum syn. R. campylogynum
'Dame Edith Sitwell' A.M. 1956 clone of R. lindleyi
danbaense sp. in subsecion TALIENSIA
danielsianum = R. 'Danielsianum'
daphniflorum syn. R. rufescens
daphnoides = R. 'Daphnoides'
'Darjeeling' clone of R. cinnabarinum ssp. cinnabarinum
dasycladoides sp. in subsection SELENSIA
dasycladum syn. R. selense ssp. dasycladum
dasycladum ssp. of R. selense ssp. of sp. in subsection SELENSIA
dasycladum var. of R. selense syn. selense ssp. dasycladum
dasylepis syn. R. beyerinckianum
dasypetalum sp. in subsection LAPPONICA
DAURICUM (Series) syn. subsection RHODORASTRA
dauricum clones
     'Arctic Pearl'
     'Fittianum'
     'Hokkaido'
     'Midwinter'
dauricum sp. in subsection RHODORASTRA
dauricum ssp. ledebourii syn. R. ledbourii
dauricum var. mucronulatum syn. R. mucronulatum var. mucronulatum
dauricum var. simpervirens syn. R. ledebourii
dauricum ssp. sichotense syn. R. sichotense
davaoense var. of R. quadrasianum var. of sp. in subgenus RHODODENDRON section VIREYA
davaoense f. of R. quadrasianum syn. R. quadrasianum var. davaoense
davidii sp. in subsection FORTUNEA
davidsonianum clones
     'Caerhay's Pink'
     'Exbury Davidsonianum'
     'Lucky Hit'
     'Ruth Lyons'
     'Serenade'
     'Star Trek'
davidsonianum sp. in subsection TRIFLORA
davuricum syn. R. dauricum
dawuense sp. in subsection LAPPONICA
dealbatum ssp. of R. temenium syn. R. temenium var. dealbatum
dealbatum var. of R. temenium var. of sp. in subsection NERIIFLORA
decandrum sp. in subgenus TSUTSUSI section BRACHYCALYX
decandrum f. lasiocarpum syn. R. decandrum
decandrum v. pilosum syn. decandrum
decandrum var. of R. dilatatum syn. decandrum
decandrum var. viscistylum syn. R. viscistylum
decipiens syn. (R. hodgsonii x R. falconeri)
declivatum sp. in subsection LAPPONICA
decorum syn. R. decorum ssp. decorum
decorum ssp. diaprepes ssp. of sp. in subsection FORTUNEA
decorum ssp. decorum clones
     'Attar'
     'Gargantua'
     'Mrs. Messel'
     'Pantagruel'
decorum ssp. decorum ssp. of sp. in subsection FORTUNEA
decorum ssp. decorum var. cordatum var. of ssp. of sp. in subsection FORTUNEA
decorum ssp. decorum var. parvistigmatis var. of spp. of sp. in subsection FORTUNEA
decumbens ssp. of R. longistylum ssp. of sp. in subsection TEPHROPEPLA
decumbens = R. 'Decumbens'
deflexum syn. R. triflorum var. triflorum
degronianum f. spomtaneum syn. R. degronianum ssp. degronianum
degronianum f. variegatum syn. R. degronianum ssp. degronianum
degronianum ssp. degronianum clones
     'Ho Emma'
     'Kyushu'
     'Metternianum'
     'Oki Island'
     'Superbum'
     'Dalriada'
     'Gerald Loder'
     'Rae's Delight'
     'Metternianus'
degronianum ssp. degronianum ssp. of sp. in subsection PONTICA
degronianum syn. R. degronianum ssp. degronianum
degronianum ssp. heptamerum ssp. of sp. in subsection PONTICA
degronianum ssp. heptamerum var. heptamerum var. of ssp. of sp. in subsection PONTICA
degronianum ssp. heptamerum var. hondoense var. of ssp. of sp. in subsection PONTICA
degronianum ssp. heptamerum var. kyomaruense var. of ssp. of sp. in subsection PONTICA
degronianum ssp. heptamerum var. kyomaruense f. amagianum f. of var. of ssp. of sp. in
 &nbs; subsection PONTICA
degronianum ssp. yakushimanum ssp. of sp. in subsection PONTICA
degronianum ssp. yakushimanum var. intermedium var. of ssp. of sp. in subsection PONTICA
degronianum ssp. yakushimanum var. yakushimanum clones
     'Angel'
     'Baron Lionel'
     'Church Lane'
     'Convexum'
     'Ken Janeck'
     'Koichiro Wada'
     'Mist Maiden'
     'Montanum'
     'Parvum'
     'Pink Parasol'
     'Planum'
     'Rhodoland's Silver Mist'
     'White Velvet'
     'Yak-ity-yak'
     'Yaku Angel'
     'Yakushimanum Exbury'
degronianum ssp. yakushimanum var. yakushimanum var. of ssp. of sp. in subsection PONTICA
degronianum var. ankaii syn. R. degronianum ssp. degronianum
degronianum var. yakushimanum syn. R. degronainum ssp. degronianum var. yakushimanum
dekatanum sp. in subsection BOOTHIA
'Del James' clone of R. taggianum
delavayi syn. R. arboreum ssp. delavayi
delavayi ssp. of R. arboreum ssp. of sp. in subsection ARBOREA
delavayi var. of ssp. delavayi of R. arboreum var. of ssp. of sp. subsection ARBOREA
deleiense syn. R. tephropeplum
delicatulum var. delicatulum var. of sp. in subgenus RHODODENDRON section VIREYA subsection
    PHAEOVIREYA
delicatulum var. lanceolatoides var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection PHAEOVIREYA
deltoideum var. of R. simiarum var. of sp. in subsection ARGYROPHYLLA
'Demi-John' A.M. 1975 clone of R. johnstoneanum
dendricola sp. in subsection MADDENIA
dendritrichum syn. R. uvarifolium var. uvarifolium
dendrocharis sp. in subsection MOUPINENSIA
densifolium sp. in subgenus RHODODENDRON section VIREYA
denudatum sp. in subsection ARGYROPHYLLA
depile syn. R. oreotrephes
desquamatum syn. R. rubiginosum
deampullum sp. in section CHONIASTRUM
detersile sp. in subsection TALIENSIA
x detonsum ? R. x adenogynum
detznerianum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
devrieseanum syn. R. konori var. konori
devriesianum ssp. astrapiae syn. R. konori var. konori
diacritum syn. R. telmateium
dianthiflorum = R. 'Dianthiflorum'
dianthosmum sp. in subgenus RHODODENDRON section VIREYA subsection PHAEOVIREYA
diaprepes syn. R. decorum ssp. diaprepes
diaprepes ssp. of R. decorum ssp. of sp. in subsection FORTUNEA
dichroanthum syn. R. dichroanthum ssp. dichroanthum
dichroanthum ssp. apodectum ssp. of sp. in subsection NERIIFLORA
dichroanthum ssp. herpesticum syn. R. dichroanthum ssp. scyphocalyx
dichroanthum ssp. dichroanthum ssp. of sp. in subsection NERIIFLORA
dichroanthum ssp. scyphocalyx ssp. of sp. in subsection NERIIFLORA
dichroanthum ssp. septentrionale ssp. of sp. in subsection NERIIFLORA
dichroanthum var. apodectum syn. R. dichroanthum ssp. apodectum
dichroanthum var. scyphocalyx syn. R. dichroanthum ssp. scyphocalyx
dichroanthum var. septentrionale syn. R. dichroanthum ssp. septentrionale
dichropeplum syn. R. phaeochrysum var. levistratum
dictyotum syn. R. traillianum var. dictyotum
dictyotum var. of R. traillianum var. of sp. in subsection TALIENSIA
didymoides ssp. of sanguineum syn. R. sanguineum ssp. sanguineum var. didymoides
didymoides var. of R. sanguineum ssp. sanguineum var. of ssp. of sp. in subsection NERIIFLORA
didymoum var. of R. sanguineum syn. R. sanguineum ssp. didymum
didymum syn. R. sanguineum ssp. didymum
didymum ssp. of R. sanguineum ssp. of sp. in subsection NERIIFLORA
dielsianum (invalid) syn. R. scabrifolium var. pauciflorum
dielsianum var. dielsianum var. of sp. in subgenus RHODODENDRON section VIREYA subsection
   PHAEOVIREYA
dielsianum var. stylotrichum var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection PHAEOVIREYA
dignabile sp. in subsection TALIENSIA
dilatatum f. hypopilosum f. of sp. in subgenus TSUTSUSI section BRACHYCALYX
dilatatum sp. in subgenus TSUTSUSI section BRACHYCALYX
dilatatum var. boreale syn. R. hidakanum
dilatatum var. decandrum syn. R. decandrum
dilatatum var. kiyosumense syn. R. kiyosumense
dilatatum var. glaucum syn. R. osuzuyamense
dilatatum var. satsumense syn. decandrum
dimidiatum sp. in section PONTICA unplaced
dimitrium sp. in section PONTICA unplaced
DIMORPHICA(subsection) syn. section TSUTSUSI
diphrocalyx sp. in subsection GLISCHRA
discolor syn. R. fortunei ssp. discolor
discolor ssp. of R. fortunei ssp. of sp. in subsection FORTUNEA
discoloratum var. of R. citrinum var. of sp. in subgenus RHODODENDRON section VIREYA
disterigmoides sp. in subgenus RHODODENDRON section VIREYA
docimum ssps. of R. erythrocalyx syn. R. x erythrocaly
doctoersii syn. R. zoelleri
'Doker La' clone of R. primuliflorum
dolerum ssp. of R. selense syn. selense ssp. dasycladum
dolerum syn. R. selense ssp. dasycladum
'Doshang La' clone of R. mekongense var. mekongense
doshongense syn. R. aganniphum var. aganniphum
'Double Diamond' A.M. 1956 clone of R. johnstoneanum
'Dr. Bowan' clone of R. arboreum ?ssp.
drumonium syn. R. telmateium
dryophyllum syn. R. phaeochrysum var. levistratum
dryophyllum syn. R. phaeochrysum var. phaeochrysum
dubium syn. R. wrayi
x duclouxii syn. R. scabrifolium var. spiciferum x spinuliferum
dumicola sp. in subsection TALIENSIA
dumulosum syn. R. phaeochrysum var. agglutinatum
dunnii syn. R. henryi var. henryi
durionifolium ssp. durionifolium ssp. of sp. in subgenus RHODODENDRON section VIREYA
   subsection MALAYOVIREYA
durionifolium ssp. sabahense ssp. of sp. in subgenus RHODODENDRON section VIREYA
   subsection MALAYOVIREYA
durionifolium syn. R. fallacinum
duseimatum syn. R. calvescens var. duseimatum
duseimatum ssp. of R. selense syn. R. calvescens var. duseimatum
duseimatum var. of R. calvescens var. of sp. in subsection SELENSIA
duseimatum var. of R. selense syn. R. calvescens var. duseimatum

'Easter Island' A.M. clone of R. alutaceum var. russotinctum
'Eastern Fire' clone of R. kaempferi
ebianense sp. in subsection ARGYROPHLLA
eclecteum syn. R. eclecteum var. eclecteum
eclecteum var. bellatulum var. of sp. in subsection THOMSONIA
eclecteum var. brachyandrum syn. R. eclecteum var. eclecteum
eclecteum var. eclecteum clones
     'Kingdom Come'
eclecteum var. eclecteum var. of sp. in subsection THOMSONIA
edanoi sp. in subgenus RHODODENDRON section VIREYA subsection SOLENOVIREYA
edgarianum sp. in subsection LAPPONICA
edgarii syn. R. campanulatum ssp. campanulatum
EDGEWORTHIA subsection of section RHODODENDRON
edgeworthii clones
     'Kingdon-Ward Pink'
     'Red Collar'
     'Darjeeling Jewel'
edgeworthii sp. in subsection EDGEWORTHIA
x edinense = R. 'Edinense'
eheinense sp. in subsection MADDENIA
eglandulosum f. of R. periclymenoides syn. R. periclymeoides
eglandulosum var. of R. hedythamnum syn. R. cyanocarpum
'Ekubo' clone of R. kiusianum
elaeagnoides syn. R. lepidotum
'Elatum Group' syn. R. campylocarpum ssp. campylocarpum
'Electra' A.M. 1940 clone of R. augustinii ssp. augustinii
elegantulum sp. in subsection TALIENSIA
'Elizabeth David' clone of R. burmanicum
'Ellestee' A.M. 1959 clone of R. wardii var. wardii
elliottii clones
     'War Paint'
elliottii sp. in subsection PARISHIA
ellipticum syn. R. moulmainense
ellipticum var. leptosanthum syn. R. moulmainense
ellipticum var. of R. wrayi syn. R. wrayi
'Elsa Reid' clone of R. souliei
emaculatum syn. R. beesianum
emarginatum sp. in subgenus RHODODENDRON section VIREYA subsection PSEUDOVIREYA
emarginatum var. eriocarpum syn. R. euonymifolium
englerianum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
x enneadrum syn. R. albiflorum x ponticum
x enomotoi syn. R. macrosepalum x R. indicum
epapillatum syn. R. papillatum
epilosum var. of R. retusum var. of sp. in subgenus RHODODENDRON section VIREYA
epipastum syn. R. eudoxum var. mesopolium
epipastum ssp. of R. eudoxum syn. R. eudoxum var. mesopolium
'Epoch' clone of white R. minus var. minus
erastum sp. in subsection NERIIFLORA
eriandrum syn. R. rigidum
'Eric Rudd' A.M. 1980 clone of R. facetum
ericoides syn R. borneese ssp. angustissimum
ericoides sp. in subgenus RHODODENDRON section VIREYA subsection PSEUDOVIREYA
ericoides var. silvicolum syn R. x silvicolum
erileucum syn. R. zaleucum var. zaleucum
eriocarpum sp. in subgenus TSUTSUSI subsection TSUTSUSI
eriocarpum var. tawadae syn. R. eriocarpum
eriocarpum var. of emarginatum syn. R. euonymifolium
eriocarpum var. of indicum syn. R. eriocarpum
eriogynum syn. R. facetum
eriphyllum var. of R. cyanocarpum syn. R. cyanocarpum
eritimum syn. R. anthosphaerum
erosipetalum sp. in subgenus RHODODENDRON section VIREYA
erosum sp. in subsection BARBATA
x erythrocaly syn. R. selense x R. wardii
x erythrocalyx clones
     'Yucondus'
x erythrocalyx ssp. beimaense syn. R. selense x wardii
x erythrocalyx ssp. docimum syn R. selense x wardii
x erythrocalyx ssp. eucallum syn R. selense x wardii
x erythrocalyx ssp. truncatulum syn. R. selense x wardii
erubescens syn. R. oreodoxa var. fargesii
esetulosum sp. in subsection SELENSIA
esquirolii sp. in section CHONIASTRUM
euadenium var. of R. crinigerum var. of sp. in subsection GLISCHRA
euanthum syn. R. vernicosum
euchaites ssp. of R. neriiflorum syn. R. neriiflorum ssp. neriiflorum
eucallum ssp. of erythrocalyx syn. x erythrocalyx
euchaites syn. R. neriiflorum ssp. neriiflorum
'Euchaites Group' syn.R. neriiflorum ssp. neriiflorum
euchroum sp. in subsection NERIIFLORA
eudoxum sp. in subsection NERIIFLORA
eudoxum ssp. asteium syn. R. eudoxum var. mesopolium
eudoxum ssp. brunneifolium syn. R. eudoxum var. brunneifolium
eudoxum ssp. epipastum syn. R. eudoxum var. mesopolium
eudoxum ssp. glaphyrum syn R. temenium var. dealbatum
eudoxum ssp. pothinum syn R. temenium var. temenium
eudoxum ssp. temenium syn. R. temenium var. temenium
eudoxum ssp. trichomiscum syn. R. eudoxum var. eudoxum
eudoxum var. brunneifolium var. of sp. in subsection NERIIFLORA
eudoxum var. eudoxum var. of sp. in subsection NERIIFLORA
eudoxum var. mesopolium var. of sp. in subsection NERIIFLORA
euonymifolium sp. in subgenus RHODODENDRON section VIREYA subsection PSEUDOVIREYA
eupodum var. of R. campylogynum cultivated variant of campylogynum
EURHODODENDRON (Koch) syn. subgenus RHODODENDRON
eurysiphon sp. in subsection THOMSONIA
exasperatum sp. in subsection BARBATA
'Exbury Praestans' A.M. 1963 clone of R. praestans
'Exbury Davidsonianum' clone of R. davidsonianum
'Exbury Lutescens' clone of R. lutescens
'Exbury Pink' clone of R. souliei
'Exbury Saluenense' clone of R. saluenense ssp. saluenense
'Exbury Yakushimanum' clone of R. degronianum ssp. yakushimanun var. yakushimanum
excellens sp. in subsection MADDENIA
excelsum sp. in subsection IRRORATA
eximium ssp. of R. falconeri ssp. of sp. in subsection FALCONERA
eximium syn. R. falcoeri ssp. eximium
expositum var. of R. gaultheriifolium var. of sp. in subgenus RHODODENDRON section VIREYA
'Exquisetum' clone of R. oreotrephes
exquisetum syn. R. oreotrephes
exquisitum syn. R. sikangense var. exquisitum
exquisitum var. of R. sikangense var. sp. in subsection MACULIFERA
extraneum var. R. brookeanum ssp. brookeanum var. of ssp. of sp. in subgenus RHODODENDRON
   section VIREYA
extrorsum sp. in subgenus RHODODENDRON section VIREYA subsection PHAEOVIREYA
exuberans sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
eymae sp. in subgenus RHODODENDRON section VIREYA subsection PHAEOVIREYA

faberi syn. R. faberi ssp. faberi
faberi sp. in subsection TALIENSIA
faberi ssp. prattii syn. R. prattii
faberioides syn. R. faberi
facetum clones
     'Eric Rudd'
facetum sp. in subsection PARISHIA
'Fair Sky' clone of R. augustinii ssp. augustinii
faithae sp. in subsection FORTUNEA
'Fake' (Purple Fake) clone of R. concinnum
falcinellum syn. R. rufulum
falcinellum var. of apricum syn. R. rufulum
FALCONERA (subsection) subsection in subgenus HYMENANTHES
FALCONERI (series) syn. subsection FALCONERA
falconeri syn. R. falconeri ssp. falconeri
falconeri ssp. eximium ssp. of sp. in subsection FALCONERA
falconeri ssp. falconeri ssp. of sp. in subsection FALCONERA
fallacinum sp. in subgenus RHODODENDRON section VIREYA subsection MALAYOVIREYA
fangchengense sp. in section PONTICA subsection ARGYROPHYLLA
'Far Horizon' A.M. 1979 clone of R. principis
fargesii syn. R. oreodoxa var. fargesii
fargesii var. of R. oreodoxa var. of sp. in subsection FORTUNEA
farinosum sp. in subsection ARGYROPHYLLA
farrerae sp. in subgenus TSUTSUSI section BRACHYCALYX
farrerae var. leucotrichum syn. R. farrerae
fastigiatum sp. in subsection LAPPONICA
x fastigifolium syn. R. flammeum x R. canescens
faucium sp. in subsection THOMSONIA
fauriei f. of R. brachycaprum ssp. brachycarpum syn. R. brachycarpum ssp. fauriei f. nematoanum
fauriei syn. R. brachycarpum ssp. fauriei
fauriei ssp. of R. brachycarpum ssp. of sp. in subsection PONTICA
fauriei var. rufescens syn. R. brachycarpum ssp. brachycarpum
feddei sp. in section CHONIASTRUM
'Fernhill' clone of R. arboreum ssp. cinnamomeum var. roseum
FERRUGINEA (subsection) syn. subsection RHODODENDRON
FERRUGINEUM (series) syn. subsection RHODODENDRON
ferrugineum clones
     'Cocinea'
     'Variegatum'
ferrugineum sp. in subsection RHODODENDRON
ferrugineum ssp. kotschyi syn. R. myrtifolium
ferruginosa syn. R. lapponicum
fictolacteum syn. R. rex. ssp. fictolacteum
fictolacteum ssp. of R. rex ssp. of sp. in subsection FALCONERA
fictolacteum var. miniforme ? syn. R. rex. ssp. fictolacteum var. miniforme
filamentosum syn. R. oreadum
fimbriatum syn. R. hippophaeoides var. hippophaeoides
'Fimbriatum Group' syn. R. hippophaeoides var. hippophaeoides
'Finch' clone of R. rubiginosum
'Fine Bristles' A.M. 1955 clone of R. pubescens
fissotectum syn. R. aganniphum var. aganniphum
x fittianum syn. R. racemosum x
'Fittianum' clone of R. dauricum
'Five Arrows' ? clone of R. quinquefolium
'Fizikomachi' clone of R. kiusianum
'Flame Creeper' clone of R. indicum
flammea var. of Azalea calendulacea syn. R. flammeum
flameum sp. in subgenus PENTANTHERA section PENTANTHERA
flavantherum sp. in subsection MONANTHA
flavidum syn. R. flavidum var. flavidum
flavidum var. flavidum var. of sp. in subsection LAPPONICA
flavidum var. pilostylum var. of sp. in subsection LAPPONICA
flaviflorum syn. R. leytense var. leytense
flaviflorum var. of R. kawakamii syn. R. kawakamii
flaviflorum var. of R. zaleucum var. of sp. in subsection TRIFLORA
flavorufum syn. R. aganniphum var. flavorufum
flavorufum var. of R. aganniphum var. of sp. in subsection TALIENSIA
flavoviride sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
flavum syn. R. aureum var. aureum
flavum syn. R. luteum
flavum var. macranthum syn. R. luteum
fletcheranum clones
     'Yellow Bunting'
fletcheranum sp. in subsection MADDENIA
'Fleurie' clone of R. smithii
fleuryi sp. in subsection MADDENIA
flinckii sp. in subection LANATA
floccigerum sp. in subsection NERIIFLORA
floccigerum ssp. appropinquans syn. R. neriiflorum ssp. phaedropum
floccigerum var. appropinquans syn. R. neriiflorum ssp. phaedropum
flocculosum var. of R. thomsonii syn. R. thomsonii ssp. thomsonii
'Flore Pleno' clone of R. hirsutum
floribunda var. of Azalea viscosa syn. R. viscosum
FLORIBUNDA (subsection) syn. subsection ARGYROPHYLLA
floribundum clones
     'Swinhoe'
floribundum sp. in subsection ARGYROPHYLLA
florulentum sp. in subgenus TSUTSUSI subsection TSUTSUSI
flosculum sp. in subgenus TSUTSUSI subsection TSUTSUSI
flumineum sp. in subgenus TSUTSUSI subsection TSUTSUSI
fokienense syn. R. simiarum ssp. simiarum
'Folius Purpereus' clone of R. ponticum
'Folk's Wood' A.M. 1977 clone of R. annae
fongkaiense syn. R. mariae ssp. kwangtungense
fordii syn. R. simiarum
formosanum sp. in subsection ARGYROPHYLLA
formosanum var. of indicum syn. simsii var. simsii
formosum syn. R. formosum var. formosum
formosum var. inaequale var. of sp. in subsection MADDENIA
formosum var. formosum clones
     'Lucy Elizabeth'
formosum var. formosum var. of sp. in subsection MADDENIA
formosum var. johnstoneanum syn. R. johnstoneanum
formosum var. salicifolium syn. R. formosum var. formosum
formosum var. veitchianum syn. R. veitchianum
'Forrest's Dwarf' clone of R. racemosum
forrestii ssp. forrestii ssp. of sp. in subsection NERIIFLORA
forrestii ssp. papillatum clones
     'Carmelita'
     'Cyril Berkeley'
     'Scarlet Pimpernel'
     'Scarlet Runner'
forrestii ssp. papillatum ssp. of sp. in subsection NERIIFLORA
forrestii var. repens syn. R. forrestii ssp. forrestii
fortunans sp. in subgenus RHODODENDRON section VIREYA subsection MALAYOVIREYA
FORTUNEA (subsection) subsection in subgenus HYMENANTHES
FORTUNEI (series) syn. subsection FORTUNEA
fortunei ssp. discolor clones
     'John R. Elcock'
     'Random Harvest'
fortunei ssp. discolor ssp. of sp. in subsection FORTUNEA
fortunei ssp. fortunei clones
     'Barto's Favorite'
     'Foxy'
     'Happiness'
     'Pinë Chiffon'
     'Sir Charles Butler'
fortunei ssp. fortunei ssp. of sp. in subsection FORTUNEA
fortunei var. kwangfuense syn. fortunei ssp. discolor
foveolatum syn. R. coriaceum
'Foxy' clone of R. fortunei ssp. fortunei
FRAGARIFLORA subsection of subgenus RHODODENDRON
fragariflorum only species in subsection FRAGARIFLORA
fragrans sp. in section POGONANTHUM
fragrans syn. R. maximum
fragrans syn. R. trichostomum
franchetianum syn. R. decorum ssp. decorum
'Frank Kingdon Ward' clone of R. glischrum ssp. rude
'Frank Ludlow' F.C.C. 1974 clone of R. dalhousiae var. dalhousiae
franssenianum syn. R. villosulum
frey-wysslingii sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
x fuchsii syn R. buxifolium x lowii
fuchsii syn. x fuchsii
fuchsiifolium sp. in subgenus TSUTSUSI subsection TSUTSUSI
fuchsiiflorum syn. R. spinuliferum var. spinuliferum
fuchsioides syn R. lindaueanum var lindaueanum
'Fugennotsuki clone of R. kiusianum
'Fujimusume' clone of R. kiusianum
fulgens sp. in subsection FULGENSIA
FULGENSIA (subsection) subsection in subgenus HYMENANTHES
FULVA (subsection) subsection in subgenus HYMENANTHES
fulvastrum ssp. epipastum syn. R. eudoxum var. mesopolium
fulvastrum ssp. mesopolium syn. R. eudoxum var. mesopolium
fulvastrum ssp. trichomiscum syn. R. eudoxum var. eudoxum
fulvastrum ssp. trichophlebium syn. R. eudoxum var. eudoxum
fulvastrum var. albipetalum syn. R. eudoxum var. eudoxum
fulvoides sp. in subsection FULVA
FULVUM (series) syn. subsection FULVA
fulvum sp. in subsection FULVA
fumidum syn. R. heliolepis var. heliolepis
fumidum var. of R. heliolepis syn. R. heliolepis var. heliolepis
x furbishii syn. R. cumberlandense x R. arborescens
fuscum syn. R. malayanum var. malayanum

galactinum sp. in subsection FALCONERA
galioides syn. R. bagobonum
x gandvense syn. R. luteum x 'Mortieri'
gannanense sp. in subsection CAMPANULATA
gardenia sp. in subgenus RHODODENDRON section VIREYA subsection PHAEOVIREYA
'Gargantua' A.M. 1953 clone of R. decorum ssp. diaprepes
'Gary Herbert' clone of R. vernicosum
gaultheriifolium var. expositum var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection PSEUDOVIREYA
gaultheriifolium var. gaultheriifolium var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection PSEUDOVIREYA
gaultherioides syn. Epigaea gaultherioides
gemmiferum sp. in subsection TRIFLORA
gemmiferum syn. R. polycladum
GENESTIERIANA (subsection) subsection in subgenus RHODODENDRON
GENESTIERIANUM (subseries) syn. partly of subsection GENESTIERIANA
genestierianum only sp. in subsection GENESTIERIANA
'Geordie Sherriff' A.M. 1969 clone of R. lindleyi
'George Taylor' clone of R. araiophyllum
georgiana var. of Azalea serrulata syn. R. viscosum
georgianum var. of R. serrulatum syn. R. viscosum
'Gerald Loder' clone of R. degronianum ssp. degronianum
x geraldii clones
     'Sunte Rose'
x geraldii syn. (R. sutchuenense x R. praevernum)
geraldii var. of R. sutchuenense syn. R. x geraldii
germanicum syn. R. hirsutum
'Giant Rose' clone of R. beesianum
gibbsiae syn R. culminicolum var angiense
gibsoni syn. R. formosum var. formosum
giganteum syn. R. protistum var. giganteum
giganteum var. of R. protistum var. of sp. in subsection GRANDIA
giganteum var. siminudum syn. R. protistum var. protistum
'Gigha' A.G.M. 1969, F.C.C. 1971 clone of R. calostrotum ssp. calostrotum
gilliardii sp. in subgenus RHODODENDRON section VIREYA subsection PHAEOVIREYA
gilvum ssp. of temenium syn. R. temenium var. gilvum
gilvum var. of R. temenium var. of sp. in subsection NERIIFLORA
giraudissii syn. R. decorum
giulianettii sp. in subgenus RHODODENDRON section VIREYA subsection ALBOVIREYA
glabratum syn. R. hirsutum
glabrescens var. of R. spinuliferum var. of sp. in subsection SCABRIFOLIA
glabrifilum syn. R. macgregoriae var. glabrifilum
glabrifilum var. of R. macgregoriea var. of sp. in subgenus RHODODENDRON section VIREYA
glabriflorum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
glabriflorum var. of R. virgatum var. of sp. in subsection VIRGATA
glabrius syn. R. molle ssp. japonicum
glabrius var. aureum syn. R. molle ssp. japonicum
x gladwynense syn. R. pruniflorum x serrulatum
glandifera f. of Azalea periclymenoides syn. R. periclymenoides
glandifera var. of Azalea nudiflora syn. R. periclymenoides
glandiferum f. of R. nudiflorum syn. R. periclymenoides
glandiferum var. of R. nudiflorum syn. R. periclymenoides
glanduliferum sp. in subsection FORTUNEA
glandulistylum syn. R. wadanum
glandulostylum syn. R. guizhongense
glandulosum ssp. of R. camtschaticum ssp. of sp. in subgenus THERORHODION
glandulosum syn. R. camtschaticum ssp. glandulosum
glandulosum var. of oldhamii syn. R. oldhamii
glaphyrum syn. R. temenium var. dealbatum
glaphyrum ssp. of R. eudoxum syn. R. temenium var. dealbatum
glaphyrum ssp. of R. temenium syn. R. temenium var. dealbatum
glaucaenum unplaced
glauca var. of Azalea viscosum syn. R. viscosum
glauco-aureaum syn. R. campylogynum
glaucopeplum syn. R. aganniphum var. aganniphum
glaucopeplum var. of R. aganniphum syn. R. aganniphum var. aganniphum
glaucum f. of R. viscosum syn. R. viscosum
glaucum var. of R. dilatatum syn. R. osuzuyamense
glaucum var. of R. viscistylum syn. R. osuzuyamense
glaucum var. of R. viscosum syn. R. viscosum
GLAUCA (subsection) Subsection in subgenus RHODODENDRON
'Glaucescens Group' syn. R. haematodes ssp. chaetomaddum
glaucescens var. of R. chaetomallum syn. R. haematodes ssp. chaetomallum
glauco-aureum syn. R. campylogynum
glaucopeplum syn. R. glaucophyllum ssp. glaucophyllum
glaucophyllum ssp. glaucophyllum clones
     'Len Beer'
glaucophyllum ssp. glaucophyllum ssp. of sp. in subsection GLAUCA
glaucophyllum ssp. glaucophyllum var. album var. of ssp. of sp. in subsection GLAUCA
glaucophyllum ssp. tubiforme ssp. of sp. in subsection GLAUCA
glaucophyllum var. glaucophyllum syn. R. glaucophyllum ssp. glaucophyllum var. glaucophyllum
glaucophyllum var. luteiflorum syn. R. luteiflorum
glaucophyllum var. tubiforme syn. R. glaucophyllum ssp. tubiforme
glaucum syn. R. glaucophyllum ssp. glaucophyllum var. glaucophyllum
glaucum syn. R. viscosum
GLAUCUM (series) syn. partly of subsection GENESTIERIANA
GLAUCUM (series) syn. subsection GLAUCA
'Glen Cloy' A.M. 1960, F.C.C. 1966 clone of R. luteiflorum
'Glen Rosa' A.M. 1964 clone of R. sidereum
'Glendoick' clone of R. racemosum
GLISCHRA (subsection) subsection in subgenus HYMENANTHES
glischroides syn. R. glischrum ssp. glischroides
glischroides ssp. of R. glischrum ssp. of sp. in subsection GLISCHRA
glischroides var. arachnoideum syn. R. glischrum ssp. glischroides
glischrum syn. R. glischrum ssp. glischrum
glischrum ssp. glischroides ssp. of sp. in subsection GLISCHRA
glischrum ssp. glischrum ssp. of sp. in subsection GLISCHRA
glischrum ssp. rude clones
     'Frank Kingdon Ward'
glischrum ssp. rude ssp. of sp. in subsection GLISCHRA
glischrum var. adenosum syn. R. adenosum
GLISCHRUM subseries of BARBATUM series syn. subsection GLISCHRA
globigerum syn. R. alutaceum var. alutaceum
globigerum var. of R. roxieanum syn. R. alutaceum var. alutaceum
gloeblastum syn. R. wardii var. wardii
glomerulatum syn. R. yungningense
gloxinaeflorum syn. R. arboreum ssp. cinnamomeum var. roseum
gnaphalocarpum syn. R. mariesii
'Goat Fell' A.M. 1964 clone of R. arboreum ssp. arboreum
gongashanense sp. in subsection FORTUNEA
goodenoughii sp. in subgenus RHODODENDRON section VIREYA subsection SOLENOVIREYA
goreri sp. in subsection MADDENIA
gorumense syn. R. macgregoriae var. macregoriae
x gowenianum syn. R. 'Gowenianum'
gracile ssp. of sp. R. brookeanum in subgenus RHODODENDRON section VIREYA
gracile ssp. of R. javanicum syn. R. brookeanum ssp. gracile
gracile syn. R. longiflorum var. longiflorum
gracile syn. R. brookeanum ssp. gracile
gracile var. of brookeanum ssp. brookeanum syn. R. brookeanum ssp. gracile
gracilentum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
gracilescens var. of R. nagasakianum syn. R. nudipes ssp. R. nudipes
gracilipes syn. R. argyrophyllum ssp. hypoglaucum
GRANDE (series) syn. subsection GRANDIA
grande sp. in subsection GRANDIA
GRANDIA (subsection) subsection in subgenus HYMENANTHES
grandiflorum var. of R. thomsonii syn. R. thomsonii ssp. thomsonii
grandifolia f. of R. augustinii syn. R. augustinii ssp. chasmanthum
grandifolium var of R. lompohense syn. R. buruense
gratiosum sp. in subgenus TSUTSUSI subsection TSUTSUSI
gratum ssp. of R. rex ssp. of sp. in subsection FALCONERA
gratum syn. R. rex ssp. gratum
graveolens unplaced
'Great Laurel' clone of R. maximum
'Greenmantle' A.M. 1977 clone of R. phaeochrysum var. phaeochrysum
gregarium syn. R. culminicolum var. culminicolum
GRIERSONIANA (subsection) subsection in subgenus HYMENANTHES
GRIERSONIANUM (series) syn. with subsection GRIERSONIANA
griersonianum only sp. in subsection GRIERSONIANA
griffithianum sp. in subsection FORTUNEA
griffithianum var. aucklandii syn. R. griffithianum
griseum var. of R. uvarifolium var. of sp. in subection FULVA
groelandicum sp. in subsection LEDUM
grothhausii sp. in subsection MADDENIA
guangnanense sp. in subsection TRIFLORA
guizhongense sp. in section TSUTSUSI
'Gumpo Fancy' clone of R. simsii
'Gumpo Pink' clone of R. simsii
'Gumpo Red' clone of R. simsii
'Gumpo White' clone of R. simsii
gymnanthum syn. R. lukiangense
gymnocarpum syn. R. microgynum
'Gymnocarpum Group' syn. R. microgynum
gymnocarpum var. of R. tutcherae var. of sp. in section CHONIASTRUM
gymnogynum syn. R. anthosphaerum
gymnomiscum syn. R. primuliflorum
gynaphalocarpum syn. mariesii

'Haba Shan' clone of R. hippophaeoides var. hippophaeoides
habaense syn. R. cuneatum
habbemae sp. in subgenus RHODODENDRON section VIREYA subsection SIPHONOVIREYA
habrotrichum sp. in subsection GLISCHRA
haemaleum ssp. of R. sanguineum syn. R. sanguineum ssp. sanguineum var. haemaleum
haemaleum var. of R. sanguineum ssp. sanguineum var. of ssp. of sp. in subsection NERIIFLORA
haematocheilum syn. R. oreodoxa var. oreodoxa
haematodes ssp. chaetomallum ssp. of sp. in subsection NERIIFLORA
haematodes syn. R. haematodes ssp. haematodes
haematodes ssp. haematodes clones
     'Red Imp'
haematodes ssp. haematodes ssp. of sp. in subsection NERIIFLORA
haematodes var. calycinum syn. R. haematodes ssp. haematodes
haematodes var. hypoleucum syn. R. haematodes ssp. haematodes
haematophthalmum sp. in subgenus RHODODENDRON section VIREYA subsection PHAEOVIREYA
haemonium syn. R. anthopogon ssp. anthopogon
haemonium var. of R. anthopogon syn. R. anthopogon ssp. anthopogon
hagnoense syn. R. indicum
hainanense sp. in subgenus TSUTSUSI section TSUTSUSI
'Hakutsuru' clone of R. kiusianum
halconense f. of R. quadrasianum syn. R. quadrasianum var. rosmainifolium
x halense syn. R. ferrugineum x hirsutum
hallaisnense syn. R. yedoense var. poukhanense
hallaisnense var. of yedoense syn. R. yedoense var. poukhanense
hameliiflorum sp. in subgenus RHODODENDRON section VIREYA subsection PSEUDOVIREYA
hamondi syn. R. 'Hammondii'
hanceanum clones
     'Canton Consul'
     'Nanum'
hanceanum sp. in subsection TEPHROPEPLA
hancockii sp. in section CHONIASTRUM
'Hanekomachi' clone of R. kiusianum
'Haneotome' clone of R. kiusianum
hangzhouense sp. in section AZALEASTRUM
hannoense syn. R. indicum
hansemannii syn. R. macgregoriae var. macgregoriae
'Hanshiro' clone of R. kiusianum
haofui sp. in subsection ARGYROPHYLLA
'Happiness' clone of R. fortunei ssp. fortunei
hardingii syn. R. annae
hardyi syn. R. augustinii ssp. hardyi
hardyi ssp. of R. augustinii ssp. of sp. in subsection TRIFLORA
'Harkness' clone of R. maximum (Leach selection)
'Harp Wood' P.C. 1971 clone of R. hodgsonii
harrovianum syn. R. polylepis
hartleyi sp. in subgenus RHODODENDRON section VIREYA unplaced
'Harunosato' clone of R. kiusianum
'Harunoumi' clone of R. kiusianum
'Harunoyoi' clone of R. kiusianum
'Harusame' clone of R. kiusianum
hatamense sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
hatamense syn. R. culminicolum var. nubicola
'Hayato' clone of R. ellipticum
headfortianum syn. R. taggianum
'Heane Wood' A.M. 1972 clone of R. argyrophyllum ssp. hypoglaucum
hedyosmum sp. in section POGONANTHUM
hedyosmum var. of R. trichostomum syn. R. hedyosmum
hedythamnum syn. R. callimorphum var. callimorphum
hedythamnum var. eglandulosum syn. R. cyanocarpum
heftii syn. R. wallichii
heishuiense syn. R. tatsienense
hejiangense sp. in subgenus TSUTSUSI section TSUTSUSI
hejiangense ssp. of argyrophyllum syn. R. insigne var. hejiangense
hejiangense var. of R. insigne var. of sp. in subsection ARGYROPHYLLA
HELIOLEPIDA subsection in subgenus RHODODENDRON
heliolepis syn. R. heliolepis var. heliolepis
heliolepis var. brevistylum var. of sp. in subsection HELIOLEPIDA
heliolepis var. fumidum syn. R. heliolepis var. heliolepis
heliolepis var. heliolepis var. of sp. in subsection HELIOLEPIDA
heliolepis var. oporinum syn R. heliolepis var. heliolepis
hellwigii syn. R. agathodaemonis
hellwigii sp. in subgenus RHODODENDRON section VIREYA subsection PHAEOVIREYA
helodes sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
helvolum syn. R. phaeochrysum var. levistratum
hemidartum syn. R. pocophorum var. hemidartum
hemidartum var. of R. pocophorum var. of sp. in subsection NERIIFLORA
x hemigynum syn. R. pocophorum x R. eclecteum
hemigynum var. of R. chaetomallum syn. R. x hemigynum
hemitrichotum clones
     'Mirelle Vernimb'
hemitrichotum sp. in subsection SCABRIFOLIA
hemsleyanum sp. in subsection FORTUNEA
henanense ssp. henanense ssp. of sp. in subsection CAMPYLOCARPA
henanense ssp. lingbaoense ssp. of sp. in subsection CAMPYLOCARPA
'Henry Shilson' clone of R. arboreum ssp. arboreum
henryi var. henryi var. of sp. in section CHONIASTRUM
henryi var. pubescens var. of sp. in section CHONIASTRUM
hepaticum syn. R. florulentum
heptamerum syn. R. anthosphaerum
heptamerum ssp. of R. degronianum ssp. of sp. in section PONTICA
heptamerum var. of ssp. heptamerum of R. degronianum var. of ssp. of sp. in section PONTICA
heptamerum var. of R. metternichii syn. R. degronianum ssp. heptamerum
heptaster syn. R. konori var. konori
'Herbert Mitchell' clone of R. cerasinum
herpesticum ssp. of R. dichroanthum syn. R. dichroanthum ssp. scyphocalyx
herpesticum syn. R. dichroanthum ssp. scyphocalyx
'Herpesticum Group' syn. R. dichroanthum ssp. scyphocalyx
herzogii sp. in subgenus RHODODENDRON section VIREYA subsection SIPHONOVIREYA
hesperium syn. R. rigidum
heteroclitum sp. in section POGONANTHUM
heusseri var. of R. jasminiflorum var. of sp. in subgenus RHODODENDRON section VIREYA
heusseri var. of R. longiflorum syn. R. jasmainiflorum var. heusseri
hexamerum syn. R. vernicosum
hidaense (invalid)
hidakanum sp. in subgenus TSUTSUSI section BRACHYCALYX
'High Flier' A.M. 1968 clone of R. vesiculiferum
x hillieri = natural hybrid within subsection
himantodes var. himatodes var. of sp. in subgenus RHODODENDRON section VIREYA subsection
   MALAYOVIREYA
himantodes var. lavandulifolium var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection MALAYOVIREYA
himertum syn. R. sanguineum ssp. sanguineum var. himertum
himertum ssp. of R. sanguineum syn. R. sanguineum ssp. sanguineum var. himertum
himertum var. of R. sanguineum ssp. sanguineum var. of ssp. of sp. in subsection NERIIFLORA
'Hinazakura' clone of R. kiusianum
'Hinode' clone of R. kiusianum
hippophaeoides syn. R. hippophaeoides var. hippophaeoides
hippophaeoides var. occidentale var. of sp. in subsection LAPPONICA
hippophaeoides var. hippophaeoides clones
     'Bei-ma-shan'
     'Haba Shan'
     'Inshniach'
     'Sunningdale'
hippophaeoides var. hippophaeoides var. of sp. in subsection LAPPONICA
hirsuticostatum syn. R. augustinii ssp. chasmanthum
x hirsutiformum syn. R. ferrugineum x hirsutum
hirsutipetiolatum sp. in subsection HELIOLEPIDA
hirsutum clones
     'Flore Pleno'
hirsutum sp. in subsection RHODODENDRON
hirsutum var. of R. praeteritum var. of sp. in subsection FORTUNEA
hirtipes clones
     'Ita'
     'Peachblow' ?
hirtipes sp. in subsection SELENSIA
hirtolepidotum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
'His Lordship' A.M. 1945 clone of R. aberconwayi
hispida var. of Azalea viscosum syn. R. viscosum
hispida var. of Azalea glauca syn. R. viscosum
hispidum f. or R. viscosum syn. R. viscosum
hispidum syn. R. viscosum
hispidum syn. R. indicum
hispidum var. of R. viscosum syn. R. viscosum
'Ho Emma' A.M. 1976, F.C.C. 1982 clone of R. degronianum ssp. degronianum
HOCHENWARTIA canadensis syn. R. canadense
HOCHENWARTIA (genus) syn. subgenus PENTANTHERA section RHODORA
hodgsonii clones
     'Harp Wood'
     'Poet's Lawn'
hodgsonii sp. in subsection FALCONERA
'Hohman' clone of R. prunifolium
hoi ssp. of R. anthopoganoides ssp. of sp. in section POGONANTHUM
'Hokkaido' A.M. 1976 clone of R. dauricum
'Holker Hall' clone of R. arboreum ssp. arboreum
x holmbaense syn. R. fortunei ssp. discolor x catabiense
honbanianum syn. Enkianthus quinqueflorus
hondoense var. of ssp.heptamerum of R. degronianum var. of ssp. of sp. in section PONTICA
hondoense of R. metternichi syn. R. degronianum ssp. heptamerum var. hondoense
hondoense var. of japonoheptamerum syn. R. degronianum ssp. heptamerum var. hondense
'Honey Wood' A.M. 1971 clone of R. trichanthum
hongkongense sp. in section AZALEASTRUM
hooglandii sp. in subgenus RHODODENDRON section VIREYA subsection PHAEOVIREYA
hookeri sp. in subsection THOMSONIA
horaeum syn. R. citriniflorum var. horaeum
horaeum var. of R. citriniflorum var. of sp. in subsection NERIIFLORA
horlickianum sp. in subsection MADDENIA
hormophorum syn. R. pleistanthum
hormophorum syn. R. yunnanense
'Hormophorum Group' syn. R. yunnanense
hortense syn. R. macrosepalum
houlstonii syn. R. fortunei ssp. discolor
'Houlstonii Group' syn. R. fortunei ssp. discolor
huadingense sp. in section BRACHYCALYX
huguangense sp. in section CHONIASTRUM
huianum sp. in subsection FORTUNEA
huidongense sp. in subsection PARISHIA
huiyangense sp. in subgenus TSUTSUSI subsection TSUTSUSI
hukwangense syn. R. huguangense
'Humboldt Picotee' clone of R. occidentale
humicola syn. R. saluenense ssp. saluenense
humifusum syn. R. saluenense ssp. chameunum
hunanense sp. in subgenus TSUTSUSI section TSUTSUSI
hunanense var. mangshanicum syn. R. hunanense
hunnewellianum syn. R. hunnewellianum ssp. hunnewellianum
hunnewellianum ssp. of R. hunnewellianum ssp. of sp. in subsection ARGYROPHYLLA
hunnewellianum ssp. rockii ssp. of sp. in subsection ARGYROPHYLLA
hutchinsonianum syn. R. concinnum
hyacinthiflorum syn. R. ponticum
hyacinthosmum sp. in subgenus RHODODENDRON section VIREYA unplaced
hybridogenum sp. in subgenus RHODODENDRON section VIREYA subsection MALAYOVIREYA
x hybidum syn. R. maximum x viscosum var. glaucum
hylaeum sp. in subsection THOMSONIA
hylothreptum syn. R. anthosphaerum
HYMENANTHES japonica syn. R. degronianum ssp. heptamerum var. heptamerum
hymenanthes syn. R. degronianum ssp. heptamerum var. heptamerum
hymenanthes var. pentamerum syn. R. degronianum ssp. degronianum
HYMENANTHES (genus) syn. subgenus HYMENANTHES
HYMENANTHES (subgenus) subgenus in genus RHODODENDRON
hypenanthum syn. R. anthopogon ssp. hypenanthum
hypenanthum ssp. of R. anthopogon ssp. of sp. in section POGONANTHUM
hypenanthum var. of R. anthopogon ssp. anthopogon syn. R. anthopogon ssp. hypenanthum
hyperythrum clones
     'Omo'
hyperythrum sp. in subsection PONTICA
hypoblematosum syn. R. polyraphidoideum var. plyrphidoideum
hypoglaucum syn. R. argyrophyllum ssp. hypoglaucum
hypoglaucum ssp. of R. argyrophyllum ssp. of sp. in subsection ARGYROPHYLLA
hypolepidotum syn. R. brachyanthum ssp. hypolepidotum
hypolepidotum var. of R. brachyanthum syn. R. brachyanthum ssp. hypolepidotum
hypoleucophyllum (unplaced)
hypoleucum sp. in subsection LEDUM
hypoleucum var. of R. haematodes syn. R. haematodes ssp. haematodes
hypophaeum syn. R. tatsienense
hypopilosum f. R. dilatatum f. of sp. in subgenus TSUTSUSI section BRACHYCALYX
hypopitys syn. R. aureum var. hypopitys
hypopitys var. of R. aureum var. of sp. in subsection PONTICA
hypotrichotum syn. R. oreotrephes
hypotrichum syn. R. oreotrephes
hyugaense sp. in subgenus TSUTSUSU section BRACHYCALYX
hyugaense var. of R. viscistylum syn. hyugaense

idoneum syn. R. telmateium
ignescens var. of R. indicum syn. R. simsii var. simsii
igneum syn. R. keysii
ignicola (invalid)
x imberbe syn. R. barbatum x R. arboreum
impeditum clones
     'Moerhermii'
impeditum sp. in subsection LAPPONICA
imperator syn. R. uniflorum var. imperator
imperator var. of R. uniflorum var. of sp. in subsection UNIFLORA
impositum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
impressopunctatum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
inaequale syn. R. formosum var. inaequale
inaequale var. of R. formosum var. of sp. in subsection MADDENIA
incommodum sp. in subgenus RHODODENDRON section VIREYA subsection SIPHONOVIREYA
inconspicuum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
indicum clones
     'Balsaminaeflorum'
     'Flame Creeper'
     'Kin-no-sa'
     'Micrantha'
     'Okina Nashiki'
     'Ryde Heron' ?
indicum sp. in subgenus TSUTSUSI section TSUTSUSI
indicum syn. R. simsii
indicum var. amoenum syn. R. obtusum
indicum var. amoenum f. japonicum syn. R. kiusianum var. kiusianum
indicum var. eriocarpum syn. R. eriocarpum
indicum var. formosanum syn. R. simsii var. simsii
indicum var. ignescens syn. R. 'Ignescens'
indicum var. japonicum syn. R. kiusianum var. kiusianum
indicum var. macranthum syn. R. 'Macranthum'
indicum var. mikawanum syn. R. x transiens
indicum var. obtusum syn. R. obtusum grex
indicum var. simsii syn. R. simsii var. simsii
indicum var. sinensis syn R. scabrum ssp. scabrum
indicum var. smithii syn. x pulchrum syn. R. ledifolium x R. indicum
indicum var. sublanceolatum syn. R. scabrum ssp. scabrum
indicum var. tamurai syn. R. eriocarpum
indicum var. tawadae syn. R. eriocarpum
indicum var. kaempferi syn. R. kaempferi
indicum var. sinensis syn. R. scabrum ssp. scabrum
indicum var. sublanceolatum syn. R. scabrum ssp. scabrum
infrapilosum var. R. malayanum var. of sp. in subgenus RHODODENDRON section VIREYA
inobeanum syn. decandrum
x inopinum wasonii x
'Inshniach' clone of R. hippophaeoides var. hippophaeoides
insculptum sp. in subgenus RHODODENDRON section VIREYA subsection PSEUDOVIREYA
insigne var. insigne var. of sp. in subsection ARGYROPHYLLA
insigne var. hejiangense var. of sp. in subsection ARGYROPHYLLA
insulare var. of R. wrightianum var. of sp. in subgenus RHODODENDRON section VIREYA
insularis f. of catawbiense syn. R. catawbiense
intermedium syn. R. hirsutum x R. ferrugineum
intermedium sp. in subsection PONTICA
intermedium form of R. metternichii syn. R. degronianum ssp. yakushimanun var. intermedium
intermedium var. of R. metternichii syn. R. degronianum ssp. yakushimanum var. intermedium
intermedium var. of R. quadrasianum var.of sp. in subgenus RHODODENDRON section VIREYA
intortum syn. R. phaeochrysum var. levistratum
intranervatum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
intricatum sp. in subsection LAPPONICA
inundatum sp. in subgenus RHODODENDRON section VIREYA subsection SIPHONOVIREYA
invasorium syn. R. inconspicuum
invictum sp. in subsection HELIOLEPIDA
ioanthum syn. R. siderophyllum
ionanthum var. of R. latoucheae var. of sp. in section CHONIASTRUM
ionanthum var. of R. wilsoniae syn. R. lotoucheae var. ionanthum
iochanense syn. R. racemosum
iodes syn. R. alutaceum var. iodes
iodes var. of R. alutaceum var. of sp. in subsection TALIENSIA
IRRORATA (subsection) subsection in subgenus HYMENANTHES
irroratum ssp. irroratum clones
     'Caarse'
     'Polka Dot'
     'Spatter Paint'
irroratum ssp. irroratum ssp. of sp. in subsection IRRORATA
irroratum ssp. kontumense ssp. of sp. in subsection IRRORATA
irroratum ssp. pogonostylum ssp. of sp. in subsection IRRORATA
IRRORATUM subseries of IRRORATUM series syn. subsection IRRORATA
'Island Gem' clone of R. oreotrephes
'Ita' A.M. (1965) clone of R. hirtipes
iteophyllum syn. R. formosum var. formosum
'Iteophyllum Group' syn. R. formosum var. formosum
ixeunticum syn. R. crinigerum var. crinigerum
iyoense var. of R. kaempheri syn R. kaempheri

'Jack Hext' A.M. 1971 clone of R. spinuliferum
'Jade' clone of R. campylogynum
jahandiezii syn. R. siderophyllum
'Jane Banks' A.M. 1976 clone of R. ambiguum
'James Comber' A.M. 1973 clone of R. sanguineum ssp. sanguineum var. haemaleum
'James' Purple clone of R. concinnum
'James' White Oreotrephes' clone of R. oreotrephes
x jamesianum (invalid)
jangtzowense syn. R. dichroanthum ssp. apodectum
japonicum f. of var. amoenum of R. indicum syn. R. kiusianum var. kiusianum
japonicum ssp. of R. molle in section PENTANTHERA subsection SINENSIA
japonicum syn. R. degronianum ssp. heptamerum var. heptamerum
japonicum syn. R. molle ssp. japonicum
japonicum f. R. aureum syn. R. molle ssp. japonicum
japonicum f. canescens syn. R. molle ssp. japonicum
japonicum var. canescens syn. R. molle ssp. japonicum
japonicum var. of R. obtusum syn. R. kiusianum var. kiusianum
japonicum var. of R.indicum syn. R. kiusianum var. kiusianum
japonicum var. of R. molle syn. R. molle ssp. japonicum
japonicum var. of R. kaempferi syn. R. kiusianum var. kiusianum
japonicum var. pentamerum syn. R. degronianum ssp. degronianum
japonoheptamerum syn. R. degronianum ssp. heptamerum
japonoheptamerum var. hondoense syn. R. degronianum ssp. heptamerum var. hondense
jasminiflorum syn. R. citrinum var. cictrinum
jasmainflorum syn. R. jasminiflorum var. oblongifolium
jasminiflorum syn. R. pneumonanthum
jasminiflorum syn. R. radians var. minahasae
jasminiflorum var. copelandii var. of sp. in subgenus RHODODENDRON section VIREYA subsection
   SOLENOVIREYA
jasminiflorum var. heusseri var. of sp. in subgenus RHODODENDRON section VIREYA subsection
   SOLENOVIREYA
jasminiflorum var. jasminiflorum var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection SOLENOVIREYA
jasminiflorum var. oblongifolium var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection SOLENOVIREYA
jasminiflorum var. punctatum var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection SOLENOVIREYA
'Jaune' A.M. 1976 clone of R. brachyanthum ssp. brachyanthum
javanicum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
javanicum ssp. brookeanum syn. R. brookeanum var. brookeanum
javanicum ssp. brookeanum var. kinabaluense syn. R. brookeanum ssp. brookeanum var. kinabaluense
javanicum ssp. cockburnii syn. R. brookeanum ssp. cockburnii
javanicum ssp. gracile syn. R. brookeanum ssp. gracile
javanicum ssp. javanicum ssp. of sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
javanicum ssp. moultonii syn. R. brookeanum var. moultonii
javanicum ssp. schadenbergii ssp. of sp. in subgenus RHODODENDRON section VIREYA
   subsection VIREYA
javanicum var. javanicum var. of ssp. of sp. in subgenus RHODODENDRON section VIREYA
   subsection VIREYA
javanicum var. schadenbergii syn. javanicum ssp. schadenbergii
javanicum var. teysmannii var. ssp. of sp. in subgenus RHODODENDRON section VIREYA
   subsection VIREYA
javanicum var. tubiflorum syn. R. longiflorum var. longiflorum
javanicum syn. R. robinsonii
javanicum syn. R. celebicum
javanicum syn. R. renschianum
javanicum syn. R. multicolor syn. R. maddenii ssp. maddenii
jenkinsii syn. R. maddenii
'Jill' clone of R. lutescens
jinfuense ssp. of R. calophytum ssp. of sp. in subsection FORTUNEA
jingangshanicum sp. in subsection FORTUNEA
jinpingense sp. in subgenus TSUTSUSI subsection TSUTSUSI
jinxiuense sp. in subgenus TSUTSUSI subsection TSUTSUSI
'John R. Elcock' A.M. 1977 clone of R. fortunei ssp. discolor
'John Skrentny' clone of R. arboreum ssp. arboreum
johnstoneanum clones
     'Demi-John'
     'Double Diamond'
     'Rubeotinctum'
johnstoneanum sp. in subsection MADDENIA
'Jones' Lutescens' clone of R. lutescens
joniense sp. in subsection LAPPONICA
jucundum syn. R. selense ssp. jucundum
jucundum ssp. of R. selense ssp. of sp. in subsection SELENSIA
jucundum var. of R. selense syn. selense ssp. jucundum

kaempferi clones
     'Betty'
     'Eastern Fire'
     'Mimi'
     'Othello'
     'Pink Treasure'
     'Tubiflorum'
kaempferi sp. in subgenus TSUTSUSI section TSUTSUSI
kaempheri var. iyoense syn R. kaempheri
kaempferi var. japonicum syn. R. kiusianum var. kiusianum
kaempferi var. komatsui syn. R. kaempferi
kaempheri var. lusidusculum syn R. kaempheri
kaempferi var. macrogemma syn. R. kaempferi
kaempheri var. mikawanum syn. R. x transiens
kaempferi var. of R. indicum syn. R. kaempferi
kaempferi var. of R. scabrum syn. R. kaempferi
kaempferi var. plenum syn. R. kaempferi R. 'Plenum'
kaempferi var. purpureum syn. R. x komatsui
kaempheri var. tubidorum syn. R. kaempheri
kaliense sp. in section CHONIASTRUM
'Kallistos' clone of R. nuttallii
kalmiaefolium syn. R. 'Kalmiaefolium'
kamtschaticum ssp. glandulosum syn. R. camtschaticum ssp. glandulosum
kamtschaticum ssp. intercendens syn. R. camtschaticum ssp. camtschaticum
kamtschaticum ssp. typicum syn. R. camtschaticum ssp. camtschaticum
kamtschaticum var. pallasianum syn. R. camtschaticum ssp. camtschaticum
kamtschaticum var. pumilum syn. R. camtschaticum ssp. camtxchaticum
kanehirai sp. in subgenus TSUTSUSI section TSUTSUSI
kangdingense sp. in subsection TRIFLORA
kansuense unplaced
kasoense sp. in subsection MONANTHA
'Kathmandu' A.M. 1965 clone of R. traillianum var. dictyotum
kawakamii sp. in subgenus RHODODENDRON section VIREYA subsection PSEUDOVIREYA
kawakamii var. flaviflorum syn. R. kawakamii
x keditii syn R. rugosum x crassifolium
keiskei clones
     'Ramsey Gold'
     'Ramsey Tinsel'
     'Yaku Fairy'
keiskei sp. in subsection TRIFLORA
keleticum syn. R. calostrotum ssp. keleticum
keleticum ssp. of R. calostrotum ssp. of sp. in subsection SALUENENSIA
kemulense sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
'Ken Janeck' clone(?) of R. degronianum ssp. yakushimanum var. yakushimanum
kendrickii sp. in subsection IRRORATA
kesangiae var. album var. of sp. in subsection GRANDIA
kesangiae var. kesangiae var. of sp. in subsecion GRANDIA
x kesselringii syn. R. smirnowii x ponticum
x kewense syn. R. Kewense grex
KEYSIA section syn. subsection CINNABARINA
KEYSIA subgenus syn. subsection CINNABARINA
keysii clones
     'Unicolor'
keysii sp. in subsection CINNABARINA
keysii var. unicolor syn. R. keysii
keysseri syn. R. culminicolum var. culminicolum
kialense syn. R. przewalskii
kiangsiense sp. in subsection MADDENIA
'Kildonan' F.C.C. 1966 clone of R. magnificum
'Kim' clone of R. campylogynum
kinabaluense syn R. rugosum var. vaeve
kinabaluense var. R. brookeanum ssp. brookeanum var. of ssp. of sp. in subgenus RHODODENDRON
   section VIREYA
kinabaluense var. of ssp. brookeanum of sp. R. javanicum var. syn. R. brookeanum
   ssp. brookeanum var. kinabaluense
'Kingdom Come' A.M. 1978 clone of R. eclecteum var. eclecteum
'Kingdon-Ward Pink' clone of R. edgeworthii
kingdonii syn. R. calostrotum ssp. riparium
kingianum var. of R. arboreum syn. R. arboreum ssp. zeylanicum
kingianum var. of R. arboreum ssp. zeylanicum syn. R. arboreum ssp. zeylanicum
'Kin-no-sa' clone of R. indicum
kirkii syn. R. fortunei ssp. discolor
kirishimense var. of R. nudipes var. sp. in subgenus TSUTSUSI section BRACHYCALYX
kiyosumense var. of R. dilatatum syn. kiyosumense
kiusianum clones
     'Ayanohomare'
     'Benichidori'
     'Benisuzume'
     'Benizakuru'
     'Benizuru'
     'Chidori'
     'Ekubo'
     'Fizikomachi'
     'Fujimusume'
     'Fugennotsuki'
     'Hakutsuru'
     'Hanekomachi'
     'Hanoetome'
     'Hanshiro'
     'Harunosato'
     'Harunoyoi'
     'Harunoumi'
     'Harusame'
     'Hinazakura'
     'Hinode'
     'Kiyohime'
     'Komo Kulshan'
     'Kuroiwahaku'
     'Madonotsuki'
     'Maiogi'
     'Maioogi'
     'Miyamakikoshi'
     'Miyamamurasaki'
     'Miyamanokasumi'
     'Miyamanokatsura'
     'Miyamashikibu'
     'Miyamasusogo'
     'Miyamunokasumi'
     'Mountain Gem'
     'Mount Fuji'
     'Murasaki-shikibu'
     'Otomegokoro'
     'Sakon'
     'Shogetsu'
     'Taisenhaku'
     'Takochiko'
     'Tatsuta'
     'Tenshi'
     'Tsukushikomachi'
     'Tsurumi'
     'Ukon'
     'Unzenzakura'
     'Yabae'
     'Yufuzakura'
     'Yuugiri'
     'Yuzuki'
     'Zuiko'
kiusianum var. kiusianum var. of sp. in subgenus TSUTSUSI section TSUTSUSI
kiusianum var. sataense var. of sp. in subgenus TSUTSUSI section TSUTSUSI
'Kiyohime' clone of R. kiusianum
kiyosumense sp. in subgenus TSUTSUSI section BRACHYCALYX
kjellbergii syn. R. vanvuurenii
klossii syn. R. moulmainense
'Knaphill' A.M. 1925 clone of R. campanulatum ssp. campanulatum
x knightianum unplaced
kochii sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
'Koichiro Wada' F.C.C.1947, A.G.M.1969 clone of R. degroniaum ssp. yakushimanum var.
   yakushimanum
x komatsui syn. R. kaempferi x R. mucronatum var. reipense
komiyamae syn. R. tosaense
'Komo Kulshan' clone of R. kiusianum
kongboense sp. in subsection POGONANTHUM
konori var. konori var. of sp. in subgenus RHODODENDRON section VIREYA subsection PHAEOVIREYA
konori var. phaeopeplum var. of sp. in subgenus RHODODENDRON section VIREYA subsection
   PHAEOVIREYA
kontumense syn. R. irroratum ssp. kontumense
kontumense ssp. of R. irroratum ssp. of sp. in subsection IRRORATA
korthalsii sp. in subsection IRRORATA
x kosterianum syn. R. molle ssp. molle x ssp. japonicum
kotschyi ssp. of ferrugineum syn. R. myrtifolium
kotschyi syn. R. myrtifolium
x koudzumontanum syn. R. kaempferi var. macrogemma x tsusiophyllum
kouytchense syn. R. chrysocalyx
'Kristy' A.M. 1976 clone of R. adenogynum
'Kulu' clone of R. vernicosum
kuluense syn. R. adenosum
'Kuroiwahaku' clone of R. kiusianum
x kurokimense syn. R. aureum x R. degronianum
kwangfuense syn. R. fortunei ssp. discolor
kwangfuense var. of R. fortunei syn. fortunei ssp. discolor
kwangsiense ssp. of R. mariae ssp. of sp. in section TSUTSUSI
kwangsiense syn. R. mariae ssp. kwangsiense
kwangsiense var. obovatifolium syn. R. mariae ssp. kwangsiense
kwangsiense var. salicinum syn. R. mariae ssp. kwangsiense
kwangsiense var. subfalcatum syn. R. mariae ssp. kwangsiense
kwangtungense sp. subgenus TSUTSUSI section TSUTSUSI
kyawi sp. in subsection PARISHIA
kyomaruense var. of metternichii syn. R. degronianum ssp. heptamerum var. kyomaruense
kyomaruense var. of heptamerum ssp. of degronianum in subsection PONTICA
'Kyushu' clone of degronianum ssp. degronianum

'La Bar's White' clone of white R. catawbiense
labolengense sp. in subsection LAPPONICA
'Lackamas Blue' clone of R. augustinii ssp. augustinii
'Lackamas Cream' clone of chlorops
LACTEA (subsection [Sleumer]) syn. subsection TALIENSIA
LACTEUM (series) part of subsection TALIENSIA
lacteum var. macrophyllum syn. R. rex ssp. fictolacteum
lacteum clones
     'Blackhills'
lacteum sp. in subsection TALIENSIA
lacteum syn. R. stapfianum
lacteum var. macrophyllum syn. R. rex ssp. fictolacteum
laetevirens syn. R. concinnum
x laetevirens syn. R. Laetevirens grex
laetum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
laetum syn R. zolleri
laeve var. of R. rugosum var. sp. in subgenus RHODODENDRON section VIREYA
lagopus var. lagopus var. of sp. in subgenus TSUTSUSI section BRACHYCALYX
lagopus var. niphophilum var. of sp. in subgenus TSUTSUSI section BRACHYCALYX
lagopus var. tokushimense var. of sp. in subgenus TSUTSUSI section BRACHYCALYX
lagopus var. tsurugisanense syn. R. tsurugisanense var. tsurugisanense
lagopus var. of reticulatum syn. R. lagopus var. lagopus
lagopus var. of wadanum syn. R. lagopus var. logopus
lagunculicarpum sp. in subgenus RHODODENDRON section VIREYA subsection ALBOVIREYA
'Lakeside' A.M. 1970 clone of R. trichostomum
lamii sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
lampongum sp. in subgenus RHODODENDRON section VIREYA subsection ALBOVIREYA
lampropeplum syn. R. proteoides
lamprophyllum syn. R. ovatum
LANATA (subsection) subsection in subgenus HYMENANTHES
lanatoides sp. in subsection LANATA
lanatum sp. in subsection LANATA
lanatum var. luciferum syn. R. lanatum
lanceolatoides var. of R. delicatulum var. sp. in subgenus RHODODENDRON section VIREYA
lanceolatum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
'Lancifolium' clone of R. ponticum
lancifolium syn. R. ponticum
lancifolium syn. R. barbatum
langbianense syn. R. irroratum ssp. kontumense
lanigerum clones
     'Beta'
     'Chapel Wood'
     'Round Wood'
     'Silvia'
     'Stonehurst'
lanigerum sp. in subsection ARBOREA
lanigerum var. silvaticum syn. R. lanigerum
laojunense sp. in subsection IRRORATA
laoticum syn. R. moulmainense
lapidosum ssp. of R. araiophyllum in subsection IRRORATA
lapidosum syn R. araiophyllum ssp. lapidosum
LAPPONICA subsection in subgenus RHODODENDRON
lapponicum clones
     'Setosa'
lapponicum sp. in subsection LAPPONICA
lasiocarpum f. of decandrum syn. decandrum
lasiocarpum var. of R. stamineum var. of sp. in section CHONIASTRUM
lasiopodum syn. R. roseatum
lasiostylum sp. in subgenus TSUTSUSI section TSUTSUSI
lateriflorum sp. in subsection CINNABARINA
lateritia var. of Azalea indica syn. R. indicum
lateritium syn. R. 'Lateritium'
lateritium var. brachytrichum syn. R. 'Lateritium'
laticostum syn. R. keiskei
latifolium f. R. metternichii syn. R. degronianum ssp. heptamerum var. heptamerum
latifolium f. of var. axillare of R. malayanum f. of var. of sp. in subgenus RHODODENDRON
   section VIREYA
latifolium syn. R. maximum
latifolium syn. R. hirsutum
latifolium var. of R. lindaueanum syn R. lindaueanum var. lindaueanum
latifolium var. of R. zollingeri syn. R. zollingeri
latoucheae var. ionanthum var. of sp. in section CHONIASTRUM
latoucheae var. latoucheae var. of sp. in section CHONIASTRUM
laudandum syn. R. laudandum var. laudandum
laudandum var. laudandum var. of sp. in section POGONANTHUM
laudandum var. temoense var. of sp. in section POGONANTHUM
laureola syn. R. dielsianum var. dielsianum
lauterbachianum syn. R. macgregoriae var. macgregoriae
lavandulifolium var. of R. himantodes var. of sp. in subgenus RHODODENDRON section VIREYA
laxiflorum syn. R. annae
leachianum syn. R. lapponicum
'Leachii' clone of R. maximum
leclerei syn. R. rubiginosum
leclerei var. of R. rubiginosum syn. R. rubiginosum var. rubiginosum
ledebourii sp. in subsection RHODORASTRA
ledebourii ssp. of R. dauricum syn. R. ledbourii
ledifolium syn. R. mucronatum var. mucronatum
ledoides syn. R. trichostomum
LEDUM columbianum syn. R. columbianum
LEDUM glandulosum syn. R. glandulosum
LEDUM groenlandicum syn R. groenlandicum
LEDUM hypoleucum syn. R. hypoleucum
LEDUM macrophyllum syn. R. tolmachevii
LEDUM palustre var. palustre syn. R. tomentosum var. tomentosum
LEDUM palustre var. decubens syn. R. tomentosum var. subarcticum
LEDUM palustre var. diversipilosum syn. R. hypoleucum
LEDUM (subsection) subsection in section RHODODENDRON subgenus RHODODENDRON
LEDUM tomentosum syn. R. tomentosum var. tomentosum
'Ledoides Group' syn. R. trichostomum
ledoides var. of R. trichostomum syn. R. trichostomum
leei syn. R. faberi ssp. prattii
leiandrum var. of R. argyrophyllum syn. R. argyrophyllum ssp. nankingense
leiboense sp. in subgenus RHODODENDRON section VIREYA subsection PSEUDOVIREYA
leilungense syn. R. tatsienense var. tatsienense
leiopodum syn. R. ellipticum
leishanicum sp. in subsection WILLIAMSIANA
lemeei syn. R. lutescens
'Len Beer' clone of R. glaucophyllum
'Leonard Frisbie' clone of R. occidentale
lepidanthum syn. R. primuliflorum
lepidanthum var. of R. primuliflorum syn. R. primuliflorum
lepidanthum var. of R. yanthinum syn. R. concinnum
LEPIDORRHODIUM (subgenus) syn. subgenus RHODODENDRON
lepidostylum sp. in subsection TRICHOCLADA
LEPIDOTA (subsection) subsection in subgenus RHODODENDRON
LEPIDOTUM (Series) syn. subsection UNIFLORA
LEPIDOTUM (series) syn. partly with subsection LEPIDOTA
LEPIDOTUM (series) syn. partly with subsection BAILEYA
lepidotum clones
     'Copse Belt'
     'Obovatum'
     'Reuthe's Purple'
lepidotum var. album var. of sp. in subsection LEPIDOTA
lepidotum var. lepidotum var. of sp. in subsection LEPIDOTA
lepidotum var. minutiforme var. of sp. in subsection LEPIDOTA
LEPIPHERUM syn. with Section RHODODENDRON
leprosum syn. R. rubiginosum var. rubiginosum
leptanthum var. leptanthum var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection PHAEOVIREYA
leptanthum var. warianum var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection PHAEOVIREYA
leptanthum syn. R. moulmainense
leptobrachion sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
leptocarpum sp. in subsection BOOTHIA
leptocladon syn. R. lyi
leptomorphum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
leptopeplum sp. in subsection IRRORATA
leptosanthum syn. R. moulmainense
leptosanthum var of R. ellipticum syn. R. moulmainense
leptothrium sp. in section AZALEASTRUM
leucandrum syn. R. siderophyllum
'Leucanthum' clone of R. campylogynum var. leucanthum
leucanthum syn. R. mucronatum var. mucronatum
leucanthum var. of R. campylogynum cultivated variant of R. campylogynum
leucanthum var. of wadanum syn. R. wadanum
leucaspis clones
     'Midget'
leucaspis sp. in subsection BOOTHIA
leucobotrys syn. R. moulmainense
leucogigas sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
leucolasium syn. R. hunnewellianum ssp. hunnewellianum
leucopetalum syn. R. sanguineum ssp. sanguineum var. cloiophorum
leucopetalum ssp. of R. sanguineum syn. R. sanguineum ssp. sanguineum var. cloiophorum
leucotrichum var. of R. farrerae syn. R. farrerae
levinei sp. in subsection MADDENIA
levistratum syn. R. phaeochrysum var. levistratum
levistratum var. of R. phaeochrysum var. of sp. in subsection TALIENSIA
leytense var. leytense var. of sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
leytense var. loheri var. of sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
'Lhasa' P.C. 1971 clone of R. nuttallii
liaoxigensis sp. in subsection MICRANTHA
x liewianum syn R. rugosum x stenophyllum
liliiflorum sp. in subsection MADDENIA
limprichtii syn. R. oreodoxa var. oreodoxa
lindaueanum var. bantaengense var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection PSEUDOVIREYA
lindaueanum var. cyclopicum syn. linaueanum var. linaueanum
lindaueanum var. latifolium syn R. lindaueanum var. lindaueanum
lindaueanum var. lindaueanum var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection PSEUDOVIREYA
lindaueanum var. psilacrum syn R. lindaueanum var. lindaueanum
lindleyanum syn. R. lindleyi
lindleyi clones
     'Dame Edith Sitwell'
     'Georgie Sherriff'
lindleyi sp. in subsection MADDENIA
lineare sp. in subgenus RHODODENDRON section VIREYA subsection MALAYOVIREYA
linearicupulare sp. in section CHONIASTRUM
'Linearifolium' ? clone of R. macrosepalum
linearifolium unplaced
linearifolium var. macrosepalum syn. R. macrosepalum syn. R. stenopetalum
linearifolium var. macrosepalum f. rhodoroides syn. R. 'Rhodoroides'
linearilobum sp. in subsection MADDENIA
linearisepalum f. of scabrum syn. R. scabrum ssp. scabrum
lingbaoense ssp. of R. henanense ssp. of sp. in subsection CAMPYLOCARPA
lingii syn. R. rhuyuenense
lingzhiense var. of R. tanastylum var. of sp. in subsection IRRORATA
linnaeoides syn. R. anagalliflorum
liratum syn. R. dichroanthum ssp. apodectum
litangense syn. R. impeditum
litchiifolium sp. in subgenus TSUTSUSI section TSUTSUSI
lithophilum syn. R. trichocladum
litiense syn. R. wardii var. wardii
'Litiense Group' syn. R. wardii var. wardii
'Little Amy' clone of R. campylogynum
liukiuense syn. R. scabrum ssp. scabrum
'Liz Ann' clone of R. sargentianum
lobbii syn. R. longiflorum var. longiflorum
loboense sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
lochae syn. R. lochiae
lochiae sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
'Loch Eck' A.M. 1974 clone of R. vernicosum
x lochmium possibly syn. (R. trichanthum x R. davidsonianum)
loerzingii sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
loheri syn. R. leytense var. loheri
loheri var. of R. leytense var of sp. in subgenus RHODODENDRON section VIREYA
'Lois Jean' clone of R. lutescens
lompohense sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
lompohense var. grandifolium syn. R. buruense
longesquamatum sp. in subsection MACULIFERA
longicalyx sp. in subsection CAMPYLOCARPA
longifalcatum sp. in subgenus TSUTSUSI
longiflora var. of R. maddenii syn. R. maddenii ssp. maddenii
longiflorum var. bancanum var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection VIREYA
longiflorum var. heusseri syn. R. jasmainiflorum var. heusseri
longiflorum var. longiflorum var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection VIREYA
longiflorum var. longipetalum var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection VIREYA
longiflorum var. subcordatum var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection VIREYA
longifolium syn. R. grande
longiperulatum sp. in subgenus TSUTSUSI section TSUTSUSI
longipetalum var. of R. longiflorum var. of sp. in subgenus RHODODENDRON section VIREYA
longipes var. chienianum var. of sp. in subsection ARGYROPHYLLA
longipes var. longipes var. of sp. in subsection ARGYROPHYLLA
longipes syn. R. longipes var. longipes
longipilosum var. of R. trichocladum var. of sp. in subsection TRICHOCLADA
longipilosum var. of R. mekongense syn. R. trichocladum var. longipilosum
longipilosum var. of R. mekongense var. of sp. in subsection TRICHOCLADA
longistylum var. of R. orthocladum var. of sp. in subsection LAPPONICA
longistylum ssp. decumbens ssp. of sp. in subsection TEPHROPEPLA
longistylum ssp. longistylum ssp. of sp. in subsection TEPHROPEPLA
loniceriflorum sp. in subgenus TSUTSUSI subsection TSUTSUSI
loniceroides var. of christi syn. R. christii
lophophorum syn. R. phaeochrysum var. agglutinatum
lophotogynum syn. R. trichocladum
'Lophotogynum Group' syn. R. trichocladum
lopsangianum syn. R. thomsonii ssp. lopsangianum
lopsangianum ssp. of R. thomsonii ssp. of sp. in subsection THOMSONIA
lapsangianum var. of R. thomsonii syn. R. thomsonii ssp. lapsangianum
loranthiflorum sp. in subgenus RHODODENDRON section VIREYA subsection SOLENOVIREYA
'Lost Horizon' A.M. 1980 clone of R. principis
loureirianum syn. Ardisia loureiriana
'Louvecienne' A.M. 1975 clone of R. rigidum
lowei syn. R. ponticum
lowii syn. R. englerianum
lowii sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
lowndesii sp.in subsection LEPIDOTA
lucidum syn. R. vernicosum
lucidum syn. R. camelliiflorum
luciferum syn. R. lanatum
luciferum var. of lanatum syn. R. lanatum
'Lucky Hit' clone of davidsonianum
'Lucy Elizabeth' A.M. 1979 clone of R. formosum var. formosum
ludlowii sp. in subsection UNIFLORA
ludwigianum sp. in subsection MADDENIA
luhuoense sp. in section POGONANTHUM
lukiangense sp. in subsection IRRORATA
luraluense sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
luridum syn. R. russatum
lusidusculum syn. R. kaempferi
lusidusculum var. of R. kaempheri syn R. kaempheri
lussoniense syn. R. vidalli
lutea f. of var. villosum of R. quadrasianum syn. R. borneense ssp. villosum
luteiflorum clones
     'Glen Cloy'
luteiflorum sp. in subsection GLAUCA
luteiflorum var. of R. glaucophyllum syn. R. luteiflorum
luteo-alba var. of Azalea atlantica syn. R. atlanticum
luteo-album f. of R. atlanticum syn. R. atlanticum
luteo-album var. or R. atlanticum syn. R. atlanticum
luteosquamatum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
lutescens f. of R. roseum syn. R. austrinum
lutescens var. of R. brachycarpum syn. (R. aureum x R. brachycarpum)
lutescens clones
     'Bagshot Sands'
     'Berry's Bright Yellow'
     'Exbury Lutescens'
     'Jill'
     'Jones' Lutescens'
     'Lois Jean'
lutescens sp. in subsection TRIFLORA
LUTEUM subseries of AZALEA series syn. with section PENTANTHERA
luteum sp. in subgenus PENTANTHERA section PENTANTHERA
luteum syn. R. calendulaceum
luteum syn. R. periclymenoides
luteum var. flammeum syn. R. flammeum
luteum var. macranthum syn. R. luteum
luteum var. of nudiflorum syn. R. austrinum
lyi sp. in subsection MADDENIA
x lysolepis R. flavidum x

maboroense syn. R. baenitzianum
macabeanum sp. in subsection GRANDIA
macgregoriea var. glabrifilum var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection VIREYA
macgregoriae var. macgregoriae var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection VIREYA
macgregoriae var. mayrii var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection VIREYA
'Machrie' A.M. 1965 clone of R. meddianum
mackenzianum syn. R. moulmainense
macranthum syn. R. indicum
macranthum syn. R. maddenii
macranthum var. of R. flavum syn. R. luteum
macranthum var. of R. luteum syn. R. luteum
macrocarpos syn. R. dalhousiae var. dalhousiae
macrogemmum syn. R. kaempferi
macrogammum var. of R. kaempferi syn. R. kaempferi
macrogemmum var. of R. obtusum syn. R. kaempferi
macrophyllum var. of lacteum syn. R. rex ssp. fictolacteum
macrophyllum clones
     'Albion Ridge'
     'Brookings Deep Pink'
     'Seven Devils'
macrophyllum sp. in subsection PONTICA
macrosepalum var. linearifolium syn. R. stenopetalum
macrosepalum var. rhodoroides syn. R. 'Rhodoroides'
macrosepalum var. of linearifolium syn. R. stenopetalum
macrosiphon sp. in subgenus RHODODENDRON section VIREYA subsection SOLENOVIREYA
macrosmithii syn. R. argipeplum
macrostemon syn. R. 'Macrotemon'
MACULIFERA (subsection) subsection in subgenus HYMENANTHES
maculiferum sp. in subsection MACULIFERA
maculiferum ssp. anhweiense syn. R. anhweiense
MACULIFERUM subseries of BARBATUM series syn. subsection MACULIFERA
maddenii ssp. crassum ssp. of sp. in subsection MADDENIA
maddenii ssp. maddenii clones
     'Ascreavie'
maddenii ssp. maddenii ssp. of sp. in subsection MADDENIA
maddenii syn. R. maddenii ssp. maddenii
maddenii var. longiflora syn R. maddenii ssp. maddenii
maddenii var. obtusifolia syn. R. maddenii ssp. crassum
MADDENIA subsection of section RHODODENDRON
'Madonotsuki' clone of R. kiusianum
'Magnificum' clone of R. cinnabarinum ssp. cinnabarinum
magnificum clones
     'Kildonan'
magnificum sp. in subsection GRANDIA
magnificum syn. R. thaumasianthum
magniflorum sp. in subsection FORTUNEA
magnum var. of R. tsariense var. of sp. in subsection LANATA
x magorianum FORTUNEA subsection x
maguanense sp. in subgenus RHODODENDRON section VIREYA subsection PSEUDOVIREYA
'Mahogani Group' syn. R. triflorum var. triflorum
mahogani var. of R. triflorum syn. R. triflorum var. triflorum
'Mahogany Red' clone of mucronulatum
mainlingense sp. in secton POGONANTHUM
'Maiogi' clone of R. kiusianum
'Maioogi' clone of R. kiusianum
mairei syn. R. lacteum
maius sp. in subgenus RHODODENDRON section VIREYA subsection SOLENOVIREYA
maius var. of R. carringtoniae syn. R. maius
maiusculum var. of R. pulleanum var. sp. in subgenus RHODODENDRON section VIREYA
major var. of Azalea coccinea syn. R. calendulaceum
major var. of Azalea speciosa syn. R. calendulaceum
makinoi sp. in subsection PONTICA
malayanum syn. R. zollingeri
malayanum var. axillare var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection MALAYOVIREYA
malayanum var. axillare f. axillare f. of var. of sp. in subgenus RHODODENDRON
   section VIREYA subsection MALAYOVIREYA
malayanum var. axillare f. latifolium f. of var. of sp. in subgenus RHODODENDRON
   section VIREYA subsection MALAYOVIREYA
malayanum var. axillare f. ovatum f. of var. of sp. in subgenus RHODODENDRON
   section VIREYA subsection MALAYOVIREYA
malayanum var. infrapilosum var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection MALAYOVIREYA
malayanum var. malayanum var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection MALAYOVIREYA
malayanum var. pilosifilum var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection MALAYOVIREYA
malayanum var. pubens var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection MALAYOVIREYA
MALAYOVIREYA subsection in section VIREYA
malindangense syn. R. quadrasianum var. malindangense
malindangense var. of R. quadrasianum var. of sp. in subgenus RHODODENDRON
   section VIREYA
mallotum clones
     'Bilì Browning'
mallotum sp. in subsection NERIIFLORA
mandarinorum syn. R. fortunei ssp. discolor
x manglesii syn. R. 'Manglesii'
mangshanicum var. of hunanense syn. R. hunanense
manipurense syn. R. maddenii ssp. crassum
mannophorum syn. R. sanguineum ssp. sanguineum var. didymoides
mannophorum ssp. of cloiophorum syn. R. sanguineum ssp. sanguineum var. didymoides
manopeplum syn. R. esetulosum
'Margaret Mead' A.M. 1978 clone of R. veitchianum
'Margum Castle clone of R. arboreum ssp. delavayi var. delavayi
maoerense sp. in subsection FORTUNEA
maowenense sp. in subsection LAPPONICA
margarettae unplaced
mariae ssp. kwangsiense ssp. of sp. in subgenus TSUTSUSI section TSUTSUSI
mariae ssp. mariae ssp. of sp. in subgenus TSUTSUSI section TSUTSUSI
'Maricee' A.E. (ARS) clone of R. sargentianum
mariesii sp. in subgenus TSUTSUSI section BRACHYCALYX
'Mariko' clone of R. nakaharai
'Marine' P.A. (ARS) clone of R. augustinii ssp. augustinii
marivelesense f. of R. quadrasianum syn. R. quadrasianum var. marivelesense
marivelensense var. of R. quadrasianum var. of sp. in subgenus RHODODENDRON section VIREYA
MARTINIANA (subsection) syn. subsection SELENSIA
martinianum clones
     'Sleea'
martinianum sp. in subsection SELENSIA
matsumurai sp. in section TSUTSUSI
maximowiczianum unplaced
maximum clones
     'Ashleyi'
     'Great Laurel'
     'Harkness'
     'Leachii'
     'Mount Mitchell'
     'Nassau Red'
     'Rosebay'
     'Summertime'
maximum sp. in subsection PONTICA
maximum var. album syn. R. maximum
maximum var. purpureum syn. R. maximum
maximum syn. R. degronianum ssp. heptamerum var. heptamerum
maxumum syn. R. scabrum ssp. scabrum
maxwelii syn. R. pulchrum
maxwellii sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
mayebarae sp. in subgenus TSUTSUSI section BRACHYCALYX
mayebarae var. obsumiense syn. R. mayebarae
mayebarae var. of R. nudipes syn. R. mayebarae
mayrii var. of R. macgregoriae var. of sp. in subgenus RHODODENDRON section VIREYA
'Meadow Pond' A.M. 1963 clone of R. wardii var. wardii
meddianum syn. R. meddianum var. meddianum
meddianum var. atrokermesianum clones
     'Bennan'
meddianum var. atrokermesianum var. of sp. in subsection THOMSONIA
meddianum var. meddianum clones
     'Machrie'
meddianum var. meddianum var. of sp. in subsection THOMSONIA
medoense sp. in section AZALEASTRUM
medoense var. adenostylum syn. R. ngawchangense
megacalyx clones
     'Nutmegacalyx'
megacalyx sp. in subsection MADDENIA
megalanthum sp. in subsection THOMSONIA
megalostigma syn. R. englerianum
megaphyllum syn. R. basilicum
megeratum sp. in subsection BOOTHIA
meigeri sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
mekongense syn. R. mekongense var. mekongense
mekongense var. longipilosum syn. R. trichocladum var. longipilosum
mekongense var. melinanthum syn. R. mekongense var. mekongense
mekongense var. mekongense clones
     'Doshanç La'
     'Yellow Fellow'
mekongense var. mekongense var. of sp. in subsection TRICHOCLADA
mekongense var. rubrolineatum var. of sp. in subsection TRICHOCLADA
melanostictum syn. R. rupicola var. chryseum
melantherum sp. in subgenus RHODODENDRON section VIREYA subsection PHAEOVIREYA
melinanthum syn. R. mekongense var. melinanthum syn. R. mekongense var. mekongense
melinanthum var. of R. mekongense syn. R. mekongense var. mekongense
meliphagidum sp. in subgenus RHODODENDRON section VIREYA subsection PSEUDOVIREYA
melleum ssp. of R. sanguineum syn. sanguineum ssp. sanguineum var. himertum
mengtszense sp. in subsection IRRORATA
meridionale var. meridionale var. of sp. in subgenus TSUTSUSI subsection TSUTSUSI
meridionale var. minor var. of sp. in subgenus TSUTSUSI subsection TSUTSUSI
meridionale var. setistylum syn. R. meridionale var. meridionale
mesaeum ssp. of R. sanguineum syn. R. sanguineum ssp. sanguineum var. haemaleum
mesembrinum syn. R. simsii
mesembrinum var. of simsii var. of sp. in subgenus TSUTSUSI section TSUTSUSI
mesopolium syn. R. eudoxum var. mesopolium
mesopolium ssp. of eudoxum syn. R. eudoxum var. mesopolium
mesopolium var. of R. eudoxum var. of sp. in subsection NERIIFLORA
messatum syn. R. xanthostephanum
'Meteor' clone of R. barbatum
metrium ssp. of R. selense syn. selense ssp. selense
metrium syn. R. selense ssp. selense
'Metternianus' clone of R. degronianum ssp. degronianum
metternichii f. amagianum syn. R. degronianum ssp. heptamerum var. kyomauruense f. amagianum
metternichii f. angustifolium syn. R. makinoi
metternichii f. latifolium syn. R. degronianum ssp. heptamerum var. heptamerum
metternichii ssp. yakushimanum syn. R. degronianum ssp. yakushimanum var. yakushimanum
metternichii ssp. pentamerum syn. R. degronianum ssp. degronianum
metternichii syn. R. degronianum ssp. heptamerum var. heptamerum
metternichii var. heptamerum syn. R. degronianum ssp. heptamerum
metternichi var. hondoense syn. R. degronianum ssp. heptamerum var. hondoense
metternichi var. intermedium syn. R. degronianum ssp. yakushimanum var. intermedium
metternichii var. kyomaruense syn. R. degronianum ssp. heptamerum var. kyomaruense
metternichii var. kyomaruense f. amagianum syn. R. degronianum ssp. heptamerum var.
   kyomaruense f. amagianum
metternichii var. micranthum syn. R. degronianum ssp. heptamerum var. heptamerum
metternichii var. pentamerum syn. R. degronianum ssp. degronianum
metternichii var. yakushimanum syn. R. degronianum ssp. yakushimanum var. yakushimanum
mianningense sp. in subsection MADDENIA
'Michael McLaren' clone of R. albrechtii
'Micrantha' clone of R. indicum
MICRANTHA subsection in subgenus RHODODENDRON
MICRANTHUM (Series) syn. subsection MICRANTHA
micranthum var. of metternichii syn. R. degronianum ssp. degronianum var. heptamerum
micranthum only species in subsection MICRANTHA
microcarpum var. of R. cuneifolium var. of sp. in subgenus RHODODENDRON section VIREYA
microgynum sp. in subsection NERIIFLORA
microleucum syn. R. orthocladum var. microleucum
microleucum var. of R. orthocladum var. of sp. in subsection LAPPONICA
micromalayanum sp. in subgenus RHODODENDRON section VIREYA subsection MALAYOVIREYA
micromeres syn. R. leptocarpum
microphyton sp. in subgenus TSUTSUSI section TSUTSUSI
microphyton var. trichanthum syn. R. microphyton
microphyllum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
microphyton var. trichantum syn. R. microphyon
microterum syn. R. beesianum
'Midget' clone of R. leucaspis
'Midwinter' A.M. 1963, F.C.C. 1969 clone of R. dauricum
mikawanum var. of R. indicum syn. R. kaempferi x R. macrosepalum
mikawanum var. of R. kaempheri syn. R. x transiens
nikomontanum var. of R. chrysanthum syn. R. x nikomontanum
'Millie Mac' clone of R. austrinum
mimetes syn. R. mimetes var. mimetes
mimetes syn. R. simulans
mimetes var. mimetes var. of sp. in subsection TALIENSIA
mimetes var. simulans var. of sp. in subsection TALIENSIA
'Mimi' clone of R. kaempferi
minahasae var. of R. radians var. of sp. in subgenus RHODODENDRON section VIREYA
mindanaense sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
miniatum sp. in subsection FULGENSIA
miniforme var. of R. fictolacteum ? syn. R. rex. ssp. fictolacteum var. miniforme
minimifolium syn. R. pulleanum var. pulleanum
minor var. of R. callichilioides syn. R. wentianum
minor var. of R. meridionale var. of sp. in subgenus TSUTSUSI subsection TSUTSUSI
minor var. of R. wrayi syn. R. wrayi
minus syn. R. minus var. minus
minus var. chapmanii var. of sp. in subsection CAROLINIANA
minus var. minus clones
     'Epoch'
     'Olga'
minus var. minus var. of sp. in subsection CAROLINIANA
minutiflorum sp. in subgenus TSUTSUSI section TSUTSUSI
minutiforme var. of R. lepidotum var. of sp. in subsection LEPIDOTA
minyaense sp. in subsection LAPPONICA
mirabile syn. R. genestierianum
'Mirelle Vernimb' clone of R. hemitrichotum
mishmiense syn. R. boothii
'Mishmiense Group' syn. R. boothii
missionarum syn. R. ciliicalyx
'Mist Maiden' clone of R. degronianum ssp. yakushimanum var. yakushimanum
mitriforme var. mitriforme var. of sp. in section CHONIASTRUM
mitriforme var. setaceum var. of sp. in section CHONIASTRUM
'Miyamakikoshi' clone of R. kiusianum
'Miyamamurasaki' clone of R. kiusianum
'Miyamanokasumi' clone of R. kiusianum
'Miyamanokatsura' clone of R. kiusianum
'Miyamashikibu' clone of R. kiusianum
'Miyamasusogo' clone of R. kiusianum
'Miyamunokasumi' clone of R. kiusianum
miyazawae syn. R. tosaense
miyiense sp. in subsection FORTUNEA
mjoberii syn R. durionifolium var. durionifolium
modestum syn. R. ciliatum
'Moerhermii' clone of R. impeditum
molle ssp. molle ssp. of sp. in section PENTANTHERA subsection SINENSIA
molle ssp. japonicum ssp. of sp. in section PENTANTHERA subsection SINESIA
molle syn. molle ssp. japonicum
molle var. japonicum syn. R. molle ssp. japonicum
mollianum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
mollicomum sp. in subsection SCABRIFOLIA
mollicomum var. rockii syn. R. mollicomum
molliculum f. of R. serrulatum syn. R. viscosum
mollyanum syn. R. montroseanum
mombeigii syn. R. uvarifolium var. uvarifolium
MONANTHA subsection of subgenus RHODODENDRON
monanthum sp. in subsection MONANTHA
monodii f. of R. quadrasianum syn. R. quadrasianum var. selebicum
MONOMORPHICA(subsection) syn. section TSUTSUSI
monopeplum syn. R. esetulosum
monosematum sp. in subsection MACULIFERA
monosematum var. of R. strigillosum syn. R. monosematum
montana var. of Azalea viscosa syn. R. viscosum
montanum var. of R. polyraphidoideum var. sp. in subgenus TSUTSUSI section TSUTSUSI
montanum var. of R. viscosum syn. R. viscosum
'Montanum' clone of R. degronianum ssp. yakushimanum var. yakushimanum
montiganum sp. in subsection TALIENSIA
montroseanum clones
     'Benmore'
montroseanum sp. in subsection GRANDIA
morii sp. in subsection MACULIFERA
'Morocco' A.M. 1953 clone of R. coriaceum
morsheadianum syn. R. arboreum var. roseum 'Morsheadianum'
x morterii ? R. calendulaceum x periclymenoides
moskowskii syn. R. zoelleri
motsouense syn. R. racemosum
moulmainense clones
     'Hayato'
moulmainense sp. in section CHONIASTRUM
moultonii ssp. of R. javanicum syn. R. brookeanum var. moultonii
moultonii syn. R. brookeanum var. moultonii
moultonii var. of R. brookeanum ssp. brookeanum var. of ssp. of sp. in subgenus RHODODENDRON
   section VIREYA
'Mountain Gem' clone of R. kiusianum
'Mount Everest' clone of R. cinnabarinum ssp. cinnabarinum
'Mount Fuji' clone of R. kiusianum
'Mount Mitchell' (Leach and Gable forms) clones of R. maximum
'Mount Seven Star' clone of R. nakaharai
'Mount Siga' clone of R. vernicosum
moupinense clones
     'Pink Moupinense'
moupinense sp. subsection R. MOUPINENSIA
MOUPINENSIA subsection of subgenus RHODODENDRON
'Mrs. Messel' A.M. 1923 clone of R. decorum
mucronatum clones
     'Butheana' ?
mucronatum var. mucronatum var. of sp. in subgenus TSUTSUSI section TSUTSUSI
mucronatum var. ripense var. of sp. in subgenus TSUTSUSI section TSUTSUSI
mucronulatum var. of R. dauricum syn. R. mucronulatum var. mucronulatum
mucronulatum f. ciliatum f. of sp. in subsection RHODORASTRA
mucronulatum var. albiflorum syn. R. mucronulatum var. mucronulatum
mucronulatum var. chejuense var. of sp. in subsection RHODORASTRA
mucronulatum var. ciliatum syn. R. mucronulatum
mucronulatum clones
     'Cornelì Pink'
     'Crater's Edge'
     'Mahogany Red'
     'Pinë Panther'
     'Roseum'
     'White Brightness'
     'Winter Brightness'
     'Winter Sunset'
mucronulatum var. mucronulatum var. of sp. in subsection RHODORASTRA
muliense syn. R. rupicola var. muliense
muliense var. of R. rupicola var. of sp. in subsection LAPPONICA
multicolor sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
multicolor syn. R. citrinum var. discoloratum
multiflorum ssp. R. triflorum ssp. of sp. in subsection TRIFLORA
multinervium sp. in subgenus RHODODENDRON section VIREYA subsection SOLENOVIREYA
MUMEAZALEA (subgenus) subgenus in genus RHODODENDRON
MUMEAZALEA (section[Sleumer]) syn. subgenus MUMEAZALEA
'Murasaki-shikibu' clone of R. kiusianum
murudense syn. R. crassifolium
muscicola sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
mussoti syn. R. wardii var. wardii
myiagrum syn. R. callimorphum var. myiagrum
myiagrum var. of R. callimorphum var. of sp. in subsection CAMPYLOCARPA
myrsinifolium sp. in subgenus TSUTSUSI subsection TSUTSUSI
myrsinites sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
x myrtifolium syn. R. 'Myrtifolium'
myrtifolium sp. in subsection RHODODENDRON
myrtifolium syn. R. ponticum
myrtilloides syn. R. campylogynum
'Myrtilloides Group' syn. R. campylogynum
myrtilloides var. of R. campylogynum syn. R. campylogynum

naamkwanense var. cryptonerve var. of sp. in subgenus TSUTSUSI section TSUTSUSI
naamkwanense var. naamkwanense var. of sp. in subgenus TSUTSUSI section TSUTSUSI
nagasakianum syn. nudipes ssp. nudipes
nagasakianum var. gracilescens syn. nudipes ssp. nudipes
nanjianense sp. in subsection BOOTHIA
nakaharai clones
     'Mariko'
     'Mount Seven Star'
nakaharai sp. subgenus TSUTSUSI in section TSUTSUSI
nakaii syn. R. degronianum ssp. degronianum
nakaii var. of R. degronianum syn. R. degronianum ssp. degronianum
nakotiltum sp. in subsection TALIENSIA
'Nana' clone of R. augustinii ssp. augustinii
nankingense ssp. of R. argyrophyllum ssp. of sp. in subsection ARGYROPHYLLA
nankingense var. of R. argyrophyllum syn. R. argyrophyllum ssp. nankingense
nankotaisanense syn. R. pseudochrysanthum ssp. morii var. nankotaisanense
   or R. morii var. nankotaisanense
nanophyton var. nanophyton var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection PSEUDOVIREYA
nanophyton var. petrophilum var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection PSEUDOVIREYA
nanothamnum ssp. of R. selense syn. selense ssp. selense
nanothamnum syn. R. selense ssp. selense
nanpingense sp. in subgens TSUTSUSI subsection TSUTSUSI
'Nanum' clone ? of R. hanceanum
nanum syn. R. fastigiatum
'Nanum Group' syn. R. hanceanum
narcissiflorum syn. white double R. mucronatum var. mucronulatum 'Narcissiflorum'
'Nassau Red' clone of R. maximum
natalicium sp. in subgenus RHODODENDRON section VIREYA subsection SOLENOVIREYA
nebrities syn. R. sanguineum ssp. sanguineum var. himertum
neglectum syn. R. atlanticum
neglectum f. R. atlanticum syn. R. atlanticum
negrosense f. of R. quadrasianum syn. R. quadrasianum var. davaiebse
nematoanum f. of R. brachycarpum ssp. brachycarpum syn. R. brachycarpum
   ssp. fauriei f. nematoanum
nematoanum var. of R. brachycarpum syn. R. brachycarpum ssp. fauriei f. nematoanum
nemorosum sp. in subsection MADDENIA
nemotocalyx syn. R. moulmainense
neobritannicum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
neoglandulosum sp. in subsection LEDUM
'Nepal' A.M. 1977 clone of R. cinnabarinum ssp. cinnabarinum
nepalense syn. R. arboreum
nepalense var. of R. trichocladum syn. R. mekongense var. mekongense
NERIIFLORA (subsection) subsection in subgenus HYMENANTHES
NERIIFLORUM (series) syn. with subsection NERIIFLORA
neriiflorum ssp. agetum ssp. of sp. in subsection NERIIFLORA
neriiflorum ssp. euchaites syn. R. neriiflorum ssp. neriiflorum
neriiflorum ssp. neriiflorum clones
     'Rosevallon'
neriiflorum ssp. neriiflorum ssp. of sp. in subsection NERIIFLORA
neriiflorum ssp. phaedropum ssp. of sp. in subsection NERIIFLORA
neriiflorum ssp. phoenicodum syn. R. neriiflorum ssp. neriiflorum
neriiflorum syn. R. neriiflorum ssp. neriiflorum
neriiflorum var. agetum syn. R. neriiflorum ssp. agetum
neriiflorum var. phaedropum syn. R. neriiflorum ssp. phaedropum
neriifolium sp. in subgenus RHODODENDRON section VIREYA subsection PHAEOVIREYA
x nervulosum syn R. crassifolium x stenophyllum
x nervulosum var. exuberans syn. R. exuberans
ngawchangense sp. in section AZALEASTRUM
nhatrangense sp. in subsection TALIENSIA
midawanum var. of R. obtusum syn. R. x transiens
nieuwenhuisii sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
'Night Editor' clone of R. russatum
niphophilum ssp. of R. nudipes in subgenus TSUTSUSI section BRACHYCALYX
niphophilum var. of ssp. niphophilum of sp. nudipes in subgenus TSUTSUSI section BRACHYCALYX
nigroglandulosum sp. in subsection TALIENSIA
nigropunctatum syn. R. nivale ssp. boreale
nikoense syn. R. pentaphyllum
nikoense var. of pentaphyllum syn. R. pentaphyllum
x nikomontanum syn. (R. aureum x R. brachycarpum)
nikomontanum var. of R. chrysanthum syn. (R. aureum x R. brachycarpum)
nilagiricum syn. R. arboreum ssp. nilagiricum
nilagiricum ssp. of R. arboreum ssp. of sp. in subsection ARBOREA
ninguenense syn. R. irroratum ssp. irroratum
ninguenense syn. R. irroratum ssp. kontumense
niphargum syn. R. uvarifolium var. uvarifolium
nipholobum syn. R. stewartianum
niphophilum var. of R. lagopus var. of sp. in subgenus TSUTSUSI section BRACHYCALYX
niphophilum var. of R. nudipes ssp. niphophilum syn. R. lagopus var. niphophilum
NIPPONICUM subseries of series AZALEA syn. subgen. PENTHANTHERA section VISCIDULA
nipponicum only sp. in subgen. PENTANTHERA section VISCIDULA
nishiokae syn. R. succothii
nitens syn. R. calostrotum ssp. riparium
nitidulum syn. R. nitidulum var. nitidulum
nitidulum var. nitidulum var. of sp. in subsection LAPPONICA
nitidulum var. nubigenum syn. nitidulum var. nitidulum
nitidulum var. omeiense var. of sp. in subsection LAPPONICA
nitida var. of Azalea viscosa syn. R. viscosum
nitidum var. of R. viscosum syn. R. viscosum
nitidum syn. R. viscosum
nivale syn. R. nivale ssp. nivale
nivale ssp. australe ssp. of sp. in subsection LAPPONICA
nivale ssp. boreale ssp. of sp. in subsection LAPPONICA
nivale ssp. nivale ssp. of sp. in subsection LAPPONICA
niveum clones
     'Clyne Castle'
     'Crown Equerry'
niveum sp. in subsection ARBOREA
nmaiense syn. R. cephalanthum ssp. cephalanthum
nmaiense var. of R. cephalanthum syn. R. cephalanthum ssp. cephalanthum
nobile syn. R. barbatum
nobile syn. R. campanulatum ssp. campanulatum
x nobleanum syn. R. Nobleanum grex
nodosum syn. T. culminicolum var. culminicolum
noriakianum sp. sp. in subgenus TSUTSUSI subsection TSUTSUSI
normale f. of R. brachycarpum syn. R. brachycarpum ssp. brachycarpum
nortoniae sp. in subgenus RHODODENDRON section VIREYA subsection MALAYOVIREYA
notatum syn. R. dendricola
notiale sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
'Noyo Chief' (? hybrid) clone of R. arboreum ssp. zeylanicum
nubicola syn. R. culminicolum var. nubicola
nubicola var. of R. culminicolum var. of sp. in subgenus RHODODENDRON section VIREYA
nubigenum var. of R. nitidulum syn. R. nitidulum
nudatum var. of R. tatsienense var. of sp. in subsection TRIFLORA
nudiflorum f. album syn. R. periclymenoides
nudiflorum f. gladuliferum syn. R. periclymenoides
nudiflorum syn. R. roseum syn. R. canescens
nudiflorum coccineum syn. R. speciosum syn. R. calendulaceum
nudiflorum syn. R. periclymenoides
nudiflorum var. album syn. R. periclymenoides
nudiflorum var. coccineum syn. R. flammeum
nudiflorum var. glandiferum syn. R. periclymenoides
nudiflorum var. papilionacuem syn. R. periclymenoides
nudiflorum var. polyandrum syn. R. periclymenoides
nudiflorum var. roseum syn. R. canescens
nudipes sp. in subgenus TUSTSUSI section BRACHYCALYX
nudipes ssp. niphophilum var. lagopus syn. R. lagopus var. lagopus
nudipes ssp. niphophilum var. niphophilum syn. R. lagopus var. niphophilum
nudipes ssp. niphophilum var. tokushimense syn. R. lagopus var. tokushimense
nudipes ssp. niphophilum var. tsurugisanense syn. R. tsurugisanense var. tsurugisanense
nudipes ssp. nudipes var. tokushimense syn. R. lagopus var. tokushimense
nudipes ssp. yakumontanum syn. R. yakumontanum
nudipes var. kirishimense var. of sp. in subgenus TSUTSUSI section BRACHYCALYX
nupides var. mayebarae syn. R. mayebarae
nudipes var. nupides var. of sp. in subgenus TSUTSUSI section BRACHYCALYX
nudipes syn. R. reticulatum
nudipes var. mayebarae syn. R. mayebarae
nudipes var. of R. reticulatum syn. R. nudipes ssp. nudipes
nudipetiolatum var. of R. tsurugisanense var. of sp. in section BRACHYCALYX
nudistylum var. of R. subenerve syn. R. tsoi
'Numazu' clone of R. tashiroi
nummatum sp. in subgenus RHODODENDRON section VIREYA subsection PSEUDOVIREYA
'Nutmegacalyx' clone of R. megacalyx
nuttallii clones
     'Kallistos'
     'Lhasa'
nuttallii sp. in subsection MADDENIA
nwaiense syn. R. cephalanthum ssp. cephalanthum
nyingchiense sp. in section POGONANTHUM
nymphaeoides sp. in subsection FORTUNEA

oblancifolium sp. in subsection ARGYROPHYLLA
oblongifolium syn. R. viscosum
oblongifolium var. of R. jasminiflorum var. of sp. in subgenus RHODODENDRON section VIREYA
oblongifolium var. of R. valentinianum var. of sp. in subsection MADDENIA
oblongum ssp. of R. orbiculare ssp. of sp. in subsection FORTUNEA
oblongum syn. R. griffithianum
obovatifolium var. of kwangsiense syn. R. mariae ssp. kwangtungense
obovatum syn. R. lepidotum
'Obovatum' clone of R. lepidotum
obscurinervium syn. R. brookeanum ssp. gracile
obscurum syn. R. siderophyllum
obscurum sp. in subgenus RHODODENDRON section VIREYA subsection MALAYOVIREYA
obsumiense var. of R. mayebrae syn. R. mayebrae
OBTUSA(subsection) syn. section TSUTSUSI
obtusifolia var. of R. maddenii syn. R. maddenii ssp. crassum
obtusum ? clones
     'Amoenum'
     'Amoenum Coccineum'
     'Ramentaceum'
OBTUSUM subseries of AZALEA series syn. section TSUTSUSI
obtusum syn. R. Obtusum grex
obtusum syn. R. ponticum
obtusum syn. R. kiusianum var. sataense
obtusum syn. R. tosaense
obtusum var. of R. indicum syn. R. Obtusum grex
obtusum var. japonicum syn. R. kiusianum var. kiusianum
obtusum var. macrogemmum syn. R. kaempferi
obtusum var. midawanum syn. R. x transiens
obtusum var. tosaense syn. R. tosaense
obtusum f. amoenum syn. R. kiusianum 'Amoenum'
obtusifolium f. of R. poukhanense syn. R. kaempferi x R. macrosepalum
obtusum var. japonicum syn. R. kiusianum var. kiusianum
obtusum var. of R. indicum syn. R. obtusum
occidentale var. of R. hippophaeoides var. of sp. in subsection LAPPONICA
occidentale clones
     'Humboldt Picotee'
     'Crescent City Double'
     'Crescent City Gold'
     'Leonard Frisbie'
     'Mini Skirts'
     'Pistil Packin' Mama'
     'Pistol Pete'
     'Rogue River Bell'
     'Stagecoach Cream'
     'Stagecoach Frills'
occidentale sp. in subgenus PENTANTHERA section PENTANTHERA
occidentale var. paludosum syn. R. occidentale
occidentale var. sonomense syn. R. occidentale
'Ocelot' A.M. 1977 clone of R. parmulatum
ochraceum var. brevicarpum var. of sp. in subsection MACULIFERA
ochraceum var. ochraceum var. of sp. in subsection MACULIFERA
ochrocalyx R. x detonsum
odoratum syn R. ponticum
odoriferum syn. R. maddenii ssp. crassum
officinale syn. R. aureum var. aureum
'Oki Island' clone of degronianum ssp. degronianum
'Okina Nashiki' clone of R. indicum
oldhamii sp. in subgenus TSUTSUSI section TSUTSUSI
oldhamii var. glandulosum syn. R. oldhamii
oleifolium syn. R. virgatum ssp. oleifolium
oleifolium ssp. of R. virgatum ssp. of sp. in subsection VIRGATA
oliganthum sp. in subgenus RHODODENDRON section VIREYA subsection SOLENOVIREYA
oligocarphum sp. in subsection MACULIFERA
'Olga' clone of R. minus var. minus
ombrachares syn. R. tanastylum var. tanastylum
omeiense ssp. of R. argyrophyllum ssp. of sp. in subsection ARGYROPHYLLA
omeiense var. of argyrophyllum syn. R. argyrophyllum ssp. omeiense
omeiense var. of R. nitidulum var. of sp. in subsection LAPPONICA
'Omo' A.M. 1976 clone of R. hyperythrum
oomurasaki syn. R. pulchrum
ootrichum var. of R. rarilepidotum var. of sp. in subgenus RHODODENDRON section VIREYA
openshawianum syn. R. calophytum var. openshawianum
openshawianum var. of R. calophytum var. of sp. in subsection FORTUNEA
'Openwood' clone of R. yunnanense
oporinum syn. R. heliolepis var. heliolepos
oporinum var. of R. heliolepis syn R. heliolepis var. heliolepis
opulentum sp. in subgenus RHODODENDRON section VIREYA subsection PHAEOVIREYA
orbiculare syn. R. orbiculare ssp. orbiculare
orbiculare ssp. cardiobasis ssp. of sp. in subsection FORTUNEA
orbiculare ssp. oblongum ssp. of sp. in subsection FORTUNEA
orbiculare ssp. orbiculare clones
     'Painted Snipe'
orbiculare ssp. orbiculare ssp. of sp. in subsection FORTUNEA
orbiculatum sp. in subgenus RHODODENDRON section VIREYA subsection SOLENOVIREYA
obtusifolia var. of R. maddenii syn. R. maddenii ssp. crassum
oreadum sp. in subgenus RHODODENDRON section VIREYA subsection SOLENOVIREYA
oreinum syn. R. nivale ssp. boreale
oreites var. chlorops var. of sp. in section VIREYA subsection PSEUDOVIREYA
oreites var. oreites var. of sp. in section VIREYA subsection PSEUDOVIREYA
oreodoxa syn. R. oreodoxa var. oreodoxa
oreodoxa var. adenostylosum var. of sp. in subsection FORTUNEA
oreodoxa var. fargesii var. of sp. in subsection FORTUNEA
oreodoxa var. oreodoxa clones
     'Barto Rose'
     'Budget Farthing'
oreodoxa var. oreodoxa var. of sp. in subsection FORTUNEA
oreodoxa var. shensiense var. of sp. in subsection FORTUNEA
'Oreonastes Group' syn. R. roxieanum var. roxieanum
oreonastes var. of R. recurvum syn. R. roxieanum var. oreonastes
oreonastes var. of R. roxieanum syn. R. roxieanum var. oreonastes
oreotrephes clones
     'Exquisetum'
     'Island Gem'
     'James' White Oreotrephes'
oreotrephes sp. in subsection TRIFLORA
oreotrephoides syn. R. oreotrephes
oresbium syn. R. nivale ssp. boreale
oresterum syn. R. wardii var. wardii
'Original' clone of white R. caucasicum
orion syn. R. scortechinii
orion var. aurantiacum syn. R. longiflorum var. longiflorum
orthocladum syn. R. orthocladum var. orthocladum
x ornatissimum unplaced hybrid
x ornatum syn. R. 'Ornatum'
orthocladum var. longistylum var. of sp. in subsection LAPPONICA
orthocladum var. microleucum var. of sp. in subsection LAPPONICA
orthocladum var. orthocladum var. of sp. in subsection LAPPONICA
osakazuki syn. R. pulchrum
osmerum syn. R. russatum
OSMOTHAMNUS (genus) syn. section POGONANTHUM
OSMOTHAMNUS (section) syn. section POGONANTHUM
Osmothamnus fragrans syn. R. fragrans
Osmothamnus pallidus syn. R. fragrans
osuzuyamense sp. in subgenus TSUTSUSI section BRACHYCALYX
'Othello' clone of R. kaempferi
'Otomegokoro' clone of R. kiusianum
oulotrichum syn. R. trichocladum var. trichocladum
ovalifolium var. of R. wrightianum syn. R. simulans
ovatifolium var. of R. championae var. of sp. in section CHONIASTRUM
ovatosepalum syn. R. oldhamii
ovatum f. of var. axillare of R. malayanum f. of var. of sp. in subgenus RHODODENDRON
   section VIREYA
ovatum sp. in section AZALEASTRUM
ovatum var. prismatum syn. R. ovatum
oxycoccoides sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
oxyphyllum syn. R. moulmainense

pachycarpon sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
pachyphyllum syn. R. ziyuanense var. pachyphyllum
pachyphyllum var of R. ziyuanense var. of sp. in subsection MACULIFERA
pachypodum sp. in subsection MADDENIA
pachysanthum sp. in subsection MACULIFERA
pachysanthum var. of R. rufum syn. R. pachysanthum
pachystigma sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
pachytrichum var pachytrichum clones
     'Sesame'
pachytrichum var. pachytrichum var. of sp. in subsection MACULIFERA
pachytrichum var. tenuistylosum var. of sp. in subsection MACULIFERA
pagophilum ssp. of R. selense syn. selense ssp. selense
pagophilum syn. R. selense ssp. selense
pagophilum var. of R. selense syn. R. selense ssp. selense
'Painted Snipe' A.M. 1970 clone of R. orbiculare ssp. orbiculare
x pallescens syn. (R. racemosum x ? R. davidsonianum)
pallidum var. of R. thomsonii syn. R. x candelabrum
pallidum var. of R. cinnabarinum syn. R. cinnabarinum ssp. xanthocodon
'Pallidum Group' syn. R. cinnabarinum ssp. cinnabarinum
paludosum syn. R. nivale ssp. nivale
paludosum var. of R. occidentale syn. R. occidentale
palustre syn. R. tomentosum var. tomentosum
palustre syn. R. lapponicum
palustris var. of Azalea viscosa syn. R. viscosum
pamprotum syn. R. saluenense ssp. chameunum
pankimense syn. R. kendrickii
'Pantagruel' clone of R. decorum ssp. diaprepes
panteumorphum syn. ? R. x erythrocalyx
'Panteumorphum Group' syn. R. x erythrocalyx
papilionacea var. of Azalea nudiflora syn. R. periclymenoides
papilionacea var. of Azalea periclymenoides syn. R. periclymenoides
papilionaceum var. of R. nudiflorum syn. R. periclymenoides
papillatum ssp. of R. forrestii ssp. of sp. in subsection NERIIFLORA
papillatum sp. in subsection IRRORATA
'Papillon' A.M. 1978 clone of R. augustinii ssp. rubrum
papuanum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
papuanum syn. R. giulianettii
papyrociliare syn. R. mariae ssp. mariae
x paradoxum syn. ? R. x wiltonii
PARISHIA (subsection) subsection in subgenus HYMENANTHES
PARISHII subseries of IRRORATUM series syn. with subsection PARISHIA
parishii sp. in subsection PARISHIA
'Parkside' A.M. 1979 clone of R. charitopes ssp. charitopes
parmulatum clones
     'Ocelot'
parmulatum sp. in subsection NERIIFLORA
parryae sp. in subsection MADDENIA
'Parryae Group' ? syn. R. johnstoneanum
partita var. Azalea nudiflora syn. R. periclymenoides
partita var. of R. periclymenoides syn. R. periclymenoides
partitum syn. R. lanceolatum
parviflorum syn. R. lapponicum
parviflorum syn. R. ponticum
parvifolium var. of R. reticulatum syn. R. reticulatum
PARVIFOLIA (series) syn. partly subsection LAPPONICA
parvifolium syn. lapponicum
'Parvifolium Group' syn. R. lapponicum
parvistigmatis var. of R. decorum ssp. decroum var. of spp. of sp. in subsection FORTUNEA
parvulum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
'Parvum' clone of R. degronianum ssp. yakushimanum var. yakushimanum
parvum var. of R. roxieanum var. of sp. in subsection TALIENSIA
'Patricia' clone of R. campylogynum 'Charopoeum Group'
patulum syn. R. pemakoense
'Patulum Group' syn. R. pemakoense
pauciflorum var. calocodon var. of sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
pauciflorum var. of R. calophytum var. of sp. in subsection FORTUNEA
pauciflorum var. of R. scabrifolium var. of sp. in subsection SCABRIFOLIA
pauciflorum var. pauciflorum var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection VIREYA
'Peachblow' clone of R. hirtipes ?
pectinatum syn. R. moulmainense
x pelargoniflorum syn R. 'Pelargoniflorum'
pemakoense sp. in subsection UNIFLORA
pendulum sp. in subsection EDGEWORTHIA
pennivenium syn. R. tanastylum var. pennivenium
pennivenium var. of agastum syn. R. tanastylum var. pennivenium
pennivenium var. of R. tanastylum var. of sp. in subsection IRRORATA
x pensylvanicum syn R. atlanticum x periclymenoides
pentamerum syn. R. degronianum ssp. degronianum
pentamerum ssp. of R. metternichii syn. R. degronianum ssp. degronianum
pentamerum var. of R. hymenanthes syn. R. degronianum ssp. degronianum
pentamerum var. of R. japonicum syn. R. degronianum ssp. degronianum
pentamerum var. of R. metternichii syn. R. degronianum ssp. degronianum
PENTANTHERA subgen. of genus AZALEA syn. genus RHODODENDRON subgen. PENTANTHERA
PENTANTHERA (section) section of subgenus PENTHANTHERA
PENTANTHERA (subgenus) subgenus in genus RHODODENDRON
pentaphyllum var. nikoense syn. R. pentaphyllum var. pentaphyllum
pentaphyllum var. pentaphyllum var. of sp. in subgen. PENTANTHERA section SCIADORHODION
pentaphyllum var. roseum syn. R. pentaphyllum var. pentaphyllum
pentaphyllum var. shikokianum var. of sp. in subgen. PENTANTHERA section SCIADORHODION
perakense sp. in section VIREYA subsection PSEUDOVIREYA
peramabile syn. R. intricatum
peramoenum syn. R. arboreum ssp. delavayi var. peramoenum
peramoenum var. of ssp. delavayi of R. arboreum var. of ssp. of sp. in subsection ARBOREA
peregrinum sp. in section PONTICUM unplaced
x peregrinum galactinum x
periclymenoides f. album syn. R. periclymenoides
periclymenoides f. eglandulosum syn. R. periclymenoides
periclymenoides f. glanduliferum syn R. periclymenoides
periclymenoides sp. subgenus PENTANTHERA in section PENTANTHERA
periclymenoides var. of Azalea nudiflora syn. R. periclymenoides
periclymenoides var. coccineum syn. R. flammeum
periclymenoides var. partita syn. R. periclymenoides
perplexum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
'Perry Wood' A.M. 1967 clone of R. faberi ssp. prattii
persicinum syn. R. anthosphaerum
perulatum syn. R. microgynum
petelotii syn. R. tanastylum var. pennivenium
petilum sp. in subgenus TSUTSUSI section TSUTSUSI
petrocharis sp. in subsection MOUPINENSIA
petrophilum var. of R. nanophyton var. sp. in subgenus RHODODENDRON section VIREYA
phaedropum syn. R. neriiflorum ssp. phaedropum
phaedropum ssp. of R. neriiflorum ssp. of sp. in subsection NERIIFLORA
phaeochitum syn. R. rubellum
phaeochitum sp. in subgenus RHODODENDRON section VIREYA subsection PHAEOVIREYA
phaeochlorum syn. R. oreotrephes
phaeochristum sp. in subgenus RHODODENDRON section VIREYA subsection PHAEOVIREYA
phaeochrysum var. agglutinatum var. of sp. in subsection TALIENSIA
phaeochrysum var. levistratum var. of sp. in subsection TALIENSIA
phaeochrysum var. phaeochrysum clones
     'Corsock'
     'Greenmantle'
phaeochrysum var. phaeochrysum var. of sp. in subsection TALIENSIA
phaeopeplum syn. R. konori var. phaeopeplum
phaeopeplum var. of R. konori var. of sp. in subgenus RHODODENDRON section VIREYA
phaeops sp. in subgenus RHODODENDRON section VIREYA subsection PHAEOVIREYA
PHAEOVIREYA subsection in section VIREYA
'Phantom Rock' F.C.C. 1981 clone of R. sanguineum ssp. sanguineum var. haemaleum
'Philip Holmes' clone of R. canescens
x phoeniceum syn. R. 'Phoenicea'
phoeniceum syn. R. x pulchrum
phoeniceum f. of R. smithii syn. R. x pulchrum
phoenicodum syn. R. neriiflorum ssp. neriiflorum
phoenicodum ssp. of neriiflorum syn. R. neriiflorum ssp. neriiflorum
phoenicodum var. of R. neriiflorum syn. R. neriiflorum ssp. neriiflorum
pholidotum syn. R. heliolepis var. brevistylum
piceum syn. R. florulentum
x pictum syn. R. 'Pictum'
piercei sp. in subsection NERIIFLORA
pilicalyx syn. R. pachypodum
piliferum var. of R. wrightianum syn. R. papuanum
pilosifilum var. of R. malayanum var. sp. in subgenus RHODODENDRON section VIREYA
pilostylum sp. in subsection MACULIFERA
pilostylum var. of R. arboreum ssp. delavayi var. of ssp. of sp. in subsection ARBOREA
pilosum var. of decandrum syn. decandrum
pilovittatum syn. R. arboreum ssp. delavayi var. delavayi
pinetorum sp. in subgensu TSUTSUSI section TSUTSUSI
pingbianense sp. in subsection IRRORATA
pingianum sp. in subsection ARGYROPHYLLA
'Pink Baby' clone of R. pumilum
'Pink Chiffon' clone of R. fortunei ssp. fortunei
'Pink Fire' clone of R. x bakeri
Pink Moupinense' A.M. 1937 clone of R. moupinense
'Pink Panther' clone of R. mucronulatum
'Pink Parasol' clone of R. degronianum ssp. yakushimanum var. yakushimanum
'Pistil Packin' Mama' clone of R. occidentale
'Pink Treasure' clone of R. kaempferi
pittosporifolium syn. R. stamineum var, stamineum
x planecostatum syn. R. bagobonum x crassifolium
planecostatum syn. x planecostatum
planetum sp. in section PONTICUM unplaced
planifolium syn. R. campanulatum
'Planum' clone of R. degronianum ssp. yakushimanum var. yakushimanum
platyphyllum syn. R. cephalanthum ssp. platyphyllum
platyphyllum ssp. of R. cephalanthum ssp. of sp. in section POGONANTHUM
platyphyllum var. of R. cephalanthum syn. R. cephalanthum ssp. platyphyllum
platypodum sp. in subsection FORTUNEA
plebeium syn. R. heliolepis var. heliolepis
pleianthum sp. in subgenus RHODODENDRON section VIREYA subsection SOLENOVIREYA
pleistanthum sp. in subsection TRIFLORA
pneumonanthum sp. in subgenus RHODODENDRON section VIREYA subsection SOLENOVIREYA
plenum f. of R. kaempferi syn R. kaempferi R. 'Plenum'
plenum var. of R. kaempheri syn. R. kaempheri R. 'Plenum'
plenum f. of R. roseum syn. R. prinophyllum
PLINTHOCHROMA (genus) syn. subsection RHODODENDRON
'Plum Warner' clone of R. campylogynum
pocophorum var. hemidartum var. of sp. in subsection NERIIFLORA
pocophorum var. pocophorum clones
     'Cecil Nice'
pocophorum var. pocophorum var. of sp. in subsection NERIIFLORA
podocarpoides syn. R. purpureiflorum
poecilodermum syn. R. roxieanum var. roxieanum
'Poet's Lawn' A.M. 1964 clone of R. hodgsonii
POGONANTHUM section of subgenus RHODODENDRON
pogonophyllum sp. in section POGONANTHUM
pogonostylum syn. R. irroratum ssp. pogonostylum
pogonostylum ssp. of R. irroratum ssp. of sp. in subsection IRRORATA
poilanei syn. R. euonymifolium
polifolium syn. Andromeda polifolia
polifolium syn. R. thymifolium
poliopeplum syn. R. sanguineum ssp. sanguineum var. himertum
poliopeplum ssp. of R. himertum syn. R. sanguineum ssp. sanguineum var. himertum
'Polka Dot' A. M. 1957 clone of R. irroratum ssp. irroratum
poluninii sp. in subsection LANATA
polyandra var. of Azalea nudiflora syn. R. periclymenoides
polyandra var. of Azalea periclymenoides syn. R. periclymenoides
polyandrum syn. R. maddenii ssp. maddenii
polyandrum var. R. nudiflorum syn. R. periclymenoides
polyanthemum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
polycladum sp. in subsection LAPPONICA
polylepis sp. in subsection TRIFLORA
polyraphidoideum var. montanum var. of sp. in subgenus TSUTSUSI section TSUTSUSI
polyraphidoideum var. polyraphidoideum var. of sp. in subgenus TSUTSUSI section TSUTSUSI
polytrichum sp. in subsection MACULIFERA
pomense sp. in subsection TALIENSIA
PONTICA (subsection) subsection in subgenus HYMENANTHES
PONTICUM (section) the only section in subgenus RHODODENDRON
PONTICUM (series) syn. subsection R. PONTICA
ponticum clones
     'Aucubifolium'
     'Blue Jay'
     'Cheiranthifolium'
     'Folius Purpereus'
     'Lancifolium'
ponticum sp. in subsection PONTICA
ponticum syn. R. luteum
populare sp. in subsection THOMSONIA
poremense sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
porphyranthes sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
porphyroblastum syn. R. alutaceum var. alutaceum
porphyroblastum syn. R. roxieanum var. cucullatum
porphyrophyllum syn. R. erastum
porrosquameum syn. R. heliolepis var. brevistylum
'Postling' clone of R. cinnabarinum ssp. cinnabarinum
potaninii sp. in section PONTICUM unplaced
pothinum syn. R. temenium var. temenium
pothinum ssp. of R. eudoxum syn. R. temenium var. temenium
pothinum ssp. of R. temenium syn. R. temenium var. temenium
poukhanense syn. R. yedoense var. poukhanense
poukhanense f. obtusifolium syn. R. kaempferi x R. macrosepalum
poukhanense f. acutifolium syn. R. kaempferi x R. macrosepalum
poukhanense var. of R. yedoense var. of sp. subgenus TSUTSUSI in section TSUTSUSI
'Powell Glass' clone of white R. catawbiense
praeclarum sp. in section POGONANTHUM
praecox f. of chartophyllum syn. R. yunnanense
praestans clones
     'Exbury Praestans'
     'Sunte Rock'
praestans sp. in subsection GRANDIA
praeteritium var. hirsutum var. of sp. in subsection FORTUNEA
praeteritium var. praeteritum var. of sp. in subsection FORTUNEA
praetervisum sp. in subgenus RHODODENDRON subsection VIREYA subsection VIREYA
praevernum sp. in subsection FORTUNEA
prainianum sp. in subgenus RHODODENDRON section VIREYA subsection PHAEOVIREYA
prasinocalyx syn. R. wardii var. wardii
prattii clones
     'Perry Wood'
prattii sp. in subsection TALIENSIA
preptum sp. in subsection FALCONERA
primuliflorum clones
     'Doker La'
primuliflorum sp. in section POGONANTHUM
primuliflorum var. cephalanthoides syn. R. primuliflorum
primuliflorum var. lepidanthum syn. R. primuliflorum
primulinum syn. R. flavidum
'Prince Charming' clone of R. schlippenbachii
principis clones
     'Far Horizon'
     'Lost Horizon'
principis sp. in subsection TALIENSIA subgenus HYMENANTHES
principis var. vellereum syn. R. principis
prinophyllum clones
     'Philip Holmes'
prinophyllum sp. in subgenus PENTANTHERA section PENTANTHERA
prismatum var. of R. ovatum syn. R. ovatum
pritzelianum syn. R. micranthum
probum ssp. of R. selense syn. selense ssp. selense
probum syn. R. selense ssp. selense
probum var. of R. selense syn. R. selense ssp. selense
procerum syn. R. maximum
procumbens syn. Loiseleuria procumbens
proliferum sp. in subgenus RHODODENDRON section VIREYA subsection ALBOVIREYA
pronum sp. in subsection TALIENSIA
prophantum syn. R. kyawi
prophyroblastum syn. R. roxieanum var. cucullatum
prophyrophyllum syn. R. erastum
propinquum syn. R. rupicola var. rupicola
prostratum ssp. of R. saluenense syn. saluenense ssp. chameunum
prostratum syn. R. saluenense ssp. chameunum
'Prostratum Group' syn. R. saluenense ssp. chameunum
protandrum sp. in subgenus RHODODENDRON section VIREYA subsection SIPHONOVIREYA
proteoides sp. in subsection TALIENSIA
protistum syn. R. protistum var. protistum
protistum var. giganteum clones
     'Pukeiti'
protistum var. giganteum var. of sp. in subsection GRANDIA
protistum var. protistum var. of sp. in subsection GRANDIA
x pruhonicianum Unplaced
pruniflorum sp. in subsection GLAUCA
pruniflorum var. of R. tsangpoense syn. R. pruniflorum
prunifolium clones
     'Hohman'
     'S.D. Coleman'
     'Summer Sunset'
prunifolium sp. in subgenus PENTANTHERA section PENTANTHERA subsection PENTANTERA
przewalskii sp. in subsection TALIENSIA
psammogenes sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
PSEUDANTHODENDRON (subgenus) syn. genus RHODODENDRON subgenus PENTANTHERA
PSEUDAZALEA (subgenus) syn. subsection TRICHOCLADA
pseudobuxifolium sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
pseudochrysanthum f. rufovelutinum f. of sp. in subsection MACULIFERA
pseudochrysanthum sp. in subsection MACULIFERA
pseudochrysnathum ssp. morii var. nankotaisanense var. of ssp. of sp. in subsection
   MACULIFERA or syn. R. morii var. nankotaisanense
pseudochrysanthum ssp. morii ssp. of sp. in subsection MACULIFERA or syn. R. morii
pseudochrysanthum ssp. morii var. taitunense var. of ssp. of sp. in subsection MACULIFERA
   or syn. R. morii var. taituense
pseudociliicalyx syn. R. ciliicalyx
pseudociliipes sp. in subsection MADDENIA
pseudomurudense sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
pseudonitens syn. R. commonae
PSEUDORHODORASTRUM (subgenus) syn. partly subsection VIRGATA
PSEUDORHODORASTRUM sec. RHODOBOTRYS syn. subsection SCABRIFOLIA
PSEUDORHODORASTRUM sec. TRACHYRHODION syn. subsection SCABRIFOLIA
pseudotrichantum sp. in subgenus RHODODENDRON section VIREYA subsection SOLENOVIREYA
PSEUDOVIREYA subsection in section VIREYA
pseudoyanthinum syn. R. concinnum
pseudoyanthinum var. of R. concinnum syn. R. concinnum
psilacrum var. of R. lindaueanum syn R. lindaueanum var. lindaueanum
psilanthum sp. in subgenus RHODODENDRON section VIREYA subsection PHAEOVIREYA
psilostylum syn. R. flavidum var. psilostylum
psilostylum var. of R. flavidum var. of of sp. in subsection LAPPONICA
ptilostylum var. of R. rubiginosum var of sp. in subsection HELIOLEPIDA
pubens var. of R. malayanum var. of sp. in subgenus RHODODENDRON section VIREYA
pubescens clones
     'Fine Bristles'
pubescens sp. in subsection SCABRIFOLIA
pubescens var of Azalea viscosa syn. R. viscosum
pubescens var. of R. henryi var. of sp. in section CHONIASTRUM
pubicostatum sp. in subsection TALIENSIA
pubifolium var. of R. zaleucum var. of sp. in subsection TRIFLORA
pubigermen sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
pubigerum syn. R. oreotrephes
pubitubum sp. in subgenus RHODODENDRON section VIREYA subsection SOLENOVIREYA
pubitubum syn. R. fastigiatum
pudorinum sp. in subgenus RHODODENDRON section VIREYA subsection ALBOVIREYA
pudorosum sp. in subsection GRANDIA
pulchellum syn. R. canadense
'Pukeiti' clone of R. protistum var. giganteum
x pulcherrimum syn. R. 'Pulcherrimum'
pulchroides sp. subgenus TSUTSUSI in section TSUTSUSI
x pulchrum syn. R. indicum x 'Ledifolia'
pulleanum var. maiusculum var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection PSEUDOVIREYA
pulleanum var. pulleanum var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection PSEUDOVIREYA
pulogense f. of R. quadrasianum syn. R. quadrasianum var. rosmarinifolium
pulogense f. of R. quadrasianum syn. R. cuneifolium var cuneifoloium
pumilum clones
     'Pink Baby'
pumilum sp. in subsection UNIFLORA
pumilum syn. R. leptocarpum
punctatum syn. R. minus var. minus
punctatum var. of R. jasminiflorum var. sp. in subgenus RHODODENDRON section VIREYA
punctifolium sp. in subsection TALIENSIA
x puniceum syn. R. 'Rosmariniflorum' x sublanceolatum
puniceum syn. R. arboreum ssp. arboreum
puniceum syn. R. pulchrum
puralbum syn. R. wardii var. puralbum
puralbum var. of R. wardii var. of sp. in subsection CAMPYLOCARPA
purdomii sp. in section PONTICUM unplaced
'Purple Emperor' clone of R. uniflorum var. imperator
'Purple Fake' syn. 'Fake'
'Purple Lustre' clone of R. concinnum
'Purple Pillow' clone of R. russatum
purpureiflorum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
'Purpurellum Group' syn. R. cinnabarinum ssp. xanthocodon
x purpureum syn. R. kaempferi x R. mucronatum var. reipense
purpureum syn. R. maximum
purpureum syn. R. arboreum
purpureum syn. R. x komatsui
purpureum var. tigrinum syn. R. maximum
purpurellum var. of R. cinnabarinum syn. R. cinnabarinum ssp. xanthocodon
purpureum var. of R. maximum syn. R. maximum
purpureum var. of R. kaempferi syn. R. kaempferi x R. mucronatum var. reipense
purpureum var. of R. maximum syn. R. maximum
purpureum var. of R. tectum syn. x komatsui
purshii syn. R. maximum
pusillum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
pycnocladum syn. R. telmateium
x pyrrhoanthum syn. R. x forrestii
pyrrhophorum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA

'Quarry Wood' A.M. 1971 clone of R. trichostomum
'Quartz' A.M. 1955 clone of R. rex ssp. rex
qianyangense sp. in subgenus TSUTSUSI section TSUTSUSI
qinghaiense sp. in subsection LAPPONICA
quadrasianum ssp. angustissimum syn. R. borneense
quadrasianum var. borneense syn R. borneense var. borneense
quadrasianum var. cuneifolium syn. R. cuneifolium var. cuneifolium
quadrasianum var. davaoense var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection PSEUDOVIREYA
quadrasianum var. intermedium var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection PSEUDOVIREYA
quadrasianum var. malindangense var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection PSEUDOVIREYA
quadrasianum var. marivelesense var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection PSEUDOVIREYA
quadrasianum var. quadrasianum var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection PSEUDOVIREYA
quadrasianum var. rosmarinifolium var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection PSEUDOVIREYA
quadrasianum var. selebicum var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection PSEUDOVIREYA
quadrasianum var. villosum syn. R. borneense
quadrasianum var. villosum f. lutea syn. R. borneense ssp. villosum
quadrasianum var. villosum f. rubra syn. R. borneense ssp. villosum
quadrasianum f. banahaoense syn. R. quadrasianum var. rosmainifolium
quadrasianum f. davaoense syn. R. quadrasianum var. davaoense
quadrasianum f. halconense syn. R. quadrasianum var. rosmainifolium
quadrasianum f. marivelesense syn. R. quadrasianum var. marivelesense
quadrasianum f. monodii syn. R. quadrasianum var. selebicum
quadrasianum f. negrosense syn. R. quadrasianum var. davaiebse
quadrasianum f. pulogense syn. R. quadrasianum var. rosmarinifolium
quadrasianum f. pulogense syn. R. cuneifolium var cuneifoloium
quinquefolium clones
     'Five Arrows' ?
quinquefolium sp. in subgen. PENTANTHERA section SCIADORHODION
quinquefolium var. roseum syn. R. pentaphyllum
quinquefolium f. speciosum f. of sp. in secton SCIADORHODION

racemosum var. of R. rigidum syn. R. rigidum
racemosum clones
     'Cox Apricot Racemosum'
     'Forrest's Dwarf'
     'Glendoick'
     'Rock Rose'
     'White Lace'
racemosum sp. in subsection SCABRIFOLIA
racemosum var. rigidum syn. R. rigidum
radendum sp. in section POGONANTHUM
radians var. minahasae var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection SOLENOVIREYA
radians var. radians var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection SOLENOVIREYA
radicans syn. R. calostrotum ssp. keleticum
'Radicans Group' syn. R. calostrotum ssp. keleticum
radinum syn. R. trichostomum
radinum var. of R. trichostomum syn R. trichostomum
'Radinum Group' syn. R. trichostomum
radinum var. of R. trichostomum syn. R. trichostomum
'Rae Berry' clone of R. trichostomum
'Rae's Delight' clone of R. degronianum ssp. degronianum
'Ralph Clarke' clone of R. tosaense
'Ramentaceum' clone of R. obtusum
ramentaceum syn. R. 'Album'
ramipilosum sp. in subsection THOMSONIA
ramosissimum syn. R. nivale ssp. boreale
'Ramsay Gold' clone of R. keiskei
ramsdenianum sp. in subsection IRRORATA
'Ramsey Tinsel' clone of R. keiskei
randaiensse syn. R. rubropilosum
rappardii sp. in subgenus RHODODENDRON section VIREYA subsection PHAEOVIREYA
'Random Harvest' A.M. 1981 clone of R. fortunei ssp. discolor
rarile syn. R. decorum ssp. diaprepes
rarilepidotum var. ootrichum var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection VIREYA
rarilepidotum var. rarilepidotum var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection VIREYA
rarosquameum syn. R. rigidum
rarum sp. in subgenus RHODODENDRON section VIREYA subsection PHAEOVIREYA
rasile syn. R. decorum ssp. diaprepes
ravum syn. R. cuneatum
rawsonii syn. R. pulchrum
recurvoides sp. in subsection GLISCHRA
recurvum syn. R. roxieanum var. roxieanum
recurvum var. oreonastes syn. R. roxieanum var. oreonastes
'Red Collar' clone of R. edgeworthii
'Red Imp' clone of R. haematodes ssp. haematodes
redowskianum sp. in subgenus THERORHODION
regale syn. R. basilicum
'Reginald Childs' A.M. 1976 clone of R. uvarifolium
reginaldii syn. R. oreodoxa var. oreodoxa
renschianum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
'Repens Group' syn. R. forrestii ssp. forrestii
repens syn. R. forrestii ssp. forrestii
repens var. chamaedoron syn. R. chamaethomsonii var. chamaedoron
repens var. chamaethauma syn. R. chamaethomsonii var. chamaethauma
repens var. chamaethomsonii syn. R. chamaethomsonii var. chamaethomsonii
reticulatum sp. in subgenus TSUTSUSI section BRACHYCALYX
reticulatum var. bifolium syn. R. reticulatum
reticulatum var. lagopus syn. R. nupides ssp. niphophilum var. logopus
reticulatum var. nudipes syn. R. nudipes ssp. nudipes
reticulatum var. parvifolium syn. R. reticulatum
reticulatum var. wadanum syn. wadanum
retivenium sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
retusum syn. R. jasminiflorum var. heusseri
retusum syn. R. lindaueanum var. lindaueanum
retrorsipilum sp. in subgenus RHODODENDRON section VIREYA subsection SOLENOVIREYA
retusum var. epilosum var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection PSEUDOVIREYA
retusum var. retusum var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection PSEUDOVIREYA
retusum var. trichostylum var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection PSEUDOVIREYA
'Reuthe's Purple' A.M. 1967 clone of R. lepidotum
revolutum sp. in subgenus RHODODENDRON section VIREYA subsection PHAEOVIREYA
rex ssp. arizelum syn. R. arizelum
rex ssp. fictolacteum clones
     'Cherry Tip'
rex ssp. fictolacteum ssp. of sp. in subsection FALCONERA
rex ssp. gratum ssp. of sp. in subsection FALCONERA
rex ssp. rex clones
     'Quartz'
     'Roseum'
     'Ward's Rex'
rex ssp. rex ssp. of sp. in subsection FALCONERA
rex syn. R. rex ssp. rex
rhabdotum syn. R. dalhousiae var. rhabdotum
rhabdotum var. of R. dalhousiae var. of sp. in subsection MADDENIA
rhaibocarpum syn. R. selense ssp. dasycladum
rhodanthum sp. in subgenus TSUTSUSI section TSUTSUSI
rhantum syn. R. vernicosum
rhodanta f. of R. viscosum syn. R. viscosum
rhodanthum sp. in section TSUTSUSI
rhodanthum ssp. of R. temenium syn. R. eudoxum var. eudoxum
RHODOBOTRYS (section) syn. partly subsection SCABRIFOLIA
rhodochroum sp. in subgenus RHODODENDRON section VIREYA subsection PHAEOVIREYA
rhododactylum f. of wasonii syn. R. wasonii
rhododactylum syn. R. wasonii
'Rhododactylum' clone of R. wasonii
RHODODENDRON genus, subgenus and section name
RHODODENDRON sec. AZALEA syn. genus RHODODENDRON sec. PENTANTHERA
RHODODENDRON sec. PENTANTHERA syn. RHODODENDRON subgen. PENTANTHERA
RHODODENDRON subgen. PSEUDOANTHODENDRON syn. genus RHODODENDRON subgen. PENTANTHERA
'Rhodoland's Silver Mist' clone of R. degronianum ssp. yakushimanum var. yakushimanum
rhodoleucum sp. in subgenus RHODODENDRON section VIREYA subsection SOLENOVIREYA
rhodopus sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
rhodora syn. R. canadense
rhodora f. albiflora syn. R. canadense
RHODORA canadense syn. R. canadense
RHODORA (genus) syn. subgenus PENTANTHERA section RHODORA
RHODORA (section) section in subgenus PENTANTHERA
RHODORA subgenus of genus Azalea syn. subgenus PENTANTHERA section RHODORA
Rhodora canadense syn. R. canadense
Rhodora congesta syn. R. canadense
RHODORASTRA subsection of subgenus RHODODENDRON
RHODORASTRUM (section) syn. subsection RHODORASTRA
RHODORASTRUM (subgenus) syn. subsection RHODRORASTRA
rhodoroides var. of R. macrosepalum syn. R. 'Rhodoroides'
rhodosalpinx sp. in subgenus RHODODENDRON section VIREYA subsection SOLENOVIREYA
rhodostomum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
rhombicum syn. R. reticulatum
rhombicum var. albiflorum syn. R. reticulatum
rhombifolium sp. in subsection MADDENIA
rhuyuenense sp. in subgenus TSUTSUSI subsection TSUTSUSI
richardsonii var. of Azalea arborescens syn. R. arborescens
richardsonii var. of R. arborescens syn. R. arborescens
rigidum clones
     'Album'
     'Louvecienne'
rigidum sp. in subsection TRIFLORA
rigidum var. of R. racemosum syn. R. rigidum
ripaecola syn. R. naamkwanense var. naamkwanense
riparioides ssp. of R. calostrotum ssp. of sp. in subsection SALUENENSIA
riparioides var. of calostrotum syn. R. calostrotum ssp. riparioides
riparium syn. R. calostrotum ssp. riparium
riparium ssp. of R. calostrotum ssp. of sp. in subsection SALUENENSIA
ripense syn. R. mucronatum var. ripense
repense var. of mucronatum var. of sp. in subgenus TSUSTSUSI section TSUTSUSI
ripleyi var. basitrichum var. of sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
ripleyi var. cryptogonium var. of sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
ripleyi var. ripleyi var. of sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
ririei sp. in subsection ARGYROPHYLLA
'Riviera Beauty' clone of R. arboreum ssp. arboreum
rivulare sp. in subgenus TSUTSUSI section TSUTSUSI
rivulare syn. R. calostrotum var. riparium
robinsonii sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
robustum var. of R. buxifolium syn. R. buxifolium
'Rock Rose' A.M. 1970 clone of R. racemosum
rockii syn. R. hunnewellianum ssp. rockii
'Rockii Group' syn. R. mollicomum var. mollicomum
rockii ssp. of R. hunnewellianum ssp. of sp. in subsection ARGYROPHYLLA
rockii var. of R. mollicomum syn. R. mollicomum
'Roland Cooper' A.M. 1964 clone of R. campanulatum ssp. campanulatum
rollissonii syn. R. arboreum ssp. zeylanicum
'Rose Rock' see 'Rock Rose'
rosea var. of Azalea nudiflora syn. R. periclymenoides
rosea var. of Azalea nudiflora syn. R. roseum syn. R. canescens
rosea var. of R. sinense syn. R. molle ssp. japonicum
roseatum sp. in subsection MADDENIA
'Rosebay' clone of R. maximum
roseiflorum sp. in subgenus RHODODENDRON section VIREYA subsection SOLENOVIREYA
roseiflorum var. of R. brachycarpum syn. R. brachycarpum ssp. fauriei
rosendahlii sp. in subgenus RHODODENDRON section VIREYA subsection VIREY
'Rosenoble' A.M. 1973 clone of R. arboreum ssp. cinnamomeum var. roseum
roseotinctum syn. R. sanguineum ssp. sanguineum var. didymoides
roseotinctum ssp. of R. cloiophorum syn. R. sanguineum ssp. sanguineum var. didymoides
roseotinctum ssp. of R. sanguineum syn. sanguineum ssp. sanguineum var. didymoides
'Roseum' clone of R. mucronulatum
'Roseum' clone of R. rex ssp. rex
roseum f. albidum syn. R. prinophyllum
roseum f. lutescens syn. R. austrinum
roseum f. of R. suaveolens f. of sp. in subgenus RHODODENDRON section VIREYA
roseum f. of R. viscosum syn. R. viscosum
roseum f. plenum syn. R. prinophyllum
roseum syn. R. canescens
roseum var. of R. brachycarpum syn. R. brachycarpum ssp. brachycarpum
roseum var. of R. cinnamomeum ssp. of R. arboreum var. of ssp. of sp. in subsection ARBOREA
roseum var. of R. nudiflorum syn. R. canescens
roseum var. of R. pentaphyllum syn. R. pentaphyllum
roseum var. of R. quinquefolium syn. R. pentaphyllum
'Roseum', A.M. 1937, F.C.C. 1974 clone of R. arboreum ssp. cinnamomeum var. roseum
'Rosevallon' A.M. 1935 clone of R. neriiflorum
'Rosey Ball' clone of R. rubiginosum
rosmarinifolium syn. R. mucronatum var. mucronatum
rosmarinifolium var. of R. quadrasianum var. of sp. in subgenus RHODODENDRON section VIREYA
rosthornii syn. R. micranthum
rothschildii sp. in subsection FALCONERA
rotundifolium syn. R. orbiculare ssp. orbiculare
'Round Wood' A.M. 1951 clone of lanigerum
x rovellii syn. dauricum x arboreum !!!!
roxieanum syn. R. roxieanum var. roxieanum
roxieanum var. cucullatum var. of sp. in subsection TALIENSIA
roxieanum var. globigerum syn. R. alutaceum var. alutaceum
roxieanum var. oreonastes var. of sp. in subsection TALIENSIA
roxieanum var. parvum var. of sp. in subsection TALIENSIA
roxieanum var. roxieanum var. of sp. in subsection TALIENSIA
roxieoides sp. in subsection TALIENSIA
roylei syn. R. cinnabarinum ssp. cinnabarinum
'Roylei Group' syn. R. cinnabarinum ssp. cinnabarinum
roylei var. of R. cinnabarinum syn. R. cinnabarinum ssp. cinnabarinum
'Rubaiyat' A.M. 1968 clone of R. arboreum ssp. arboreum
rubellum sp. in subgenus RHODODENDRON section VIREYA subsection PHAEOVIREYA
rubescens f. of R. viscosum syn. R. viscosum
rubescens var. of Azalea viscosa syn. R. viscosum
rubescens var of R. viscosum syn. R. viscosum
rubens ssp. of R. citriniflorum syn. R. citriniflorum var. citriniflorum
rubens syn. R. citriniflorum var. citriniflorum
'Rubeotinctum' A.M. 1941 clone of R. johnstoneanum
rubicosum var. of arizelum syn. R. arizelum
rubiginosum var. leclerei syn. R. rubiginosum var. rubiginosum
rubiginosum var ptilostylum var. of sp. in subsection HELIOLEPIDA
rubiginosum var. rubiginosum clones
     'Finch'
     'Rosey Ball'
     'Wakehurst'
rubiginosum var. rubiginosum var. of sp. in subsection HELIOLEPIDA
rubineiflorum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
rubra f. of var. villosum of R. quadrasianum syn. R. borneense ssp. villosum
rubrantherum sp. in subsection MADDENIA
rubriflorum syn. R. campylogynum
rubrobracteatum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
rubropunctatum syn. R. hyperythrum
rubro-punctatum syn. R. siderophyllum
rubropunctatum syn. R. yunnanense
rubrolineatum syn. R. mekongense var. rubrolineatum
rubrolineatum var. of R. mekongense var. of sp. in subsection TRICHOCLADA
rubroluteum syn. R. viridescens
rubropilosum sp. in subgenus TSUTSUSI section TSUTSUSI
rubro-punctata syn. R. tanastylum var. lingzhiense
rubro-punctatum syn. R. siderophyllum
rubropunctatum syn. R. hyperythrum
'Rubrum Davidian' clone of R. augustinii ssp. rubrum
rubrum ssp. of R. augustinii ssp. of sp. in subsection TRIFLORA
rude syn. R. glischrum ssp. rude
rude ssp. of R. glischrum ssp. of sp. in subsection GLISHCRA
rufescens var. of fauriei syn. R. brachycarpum ssp. brachycarpum
rufescens sp. in section POGONANTHUM
rufescens syn. R. rufulum
rufo-hirtum sp. in subgenus TSUTSUSI section TSUTSUSI
rufosquamosum sp. in subsection MADDENIA
rufovelutinum f. of R. pseudochrysanthum f. of sp. in subsection MACULIFERA
rufulum sp. in subgenus TSUTSUSI subsection TSUTSUSI
rufum sp. in subsection TALIENSIA
rufum var. pachysanthum syn. R. pachysanthum
rugosum var. coriifolium syn. R. x coriifolum
rugosum var. laeve sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
rugosum var. rugosum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
rupicola var. chryseum var of sp. in subsection LAPPONICA
rupicola var. muliense var. of sp. in subsection LAPPONICA
rupicola var. rupicola var. of sp. in subsection LAPPONICA
rupivalleculatum sp. in subgenus RHODODENDRON section VIREYA
russatum clones
     'Cook's Russatum'
     'Night Editor'
     'Purple Pillow'
russatum sp. in subsection LAPPONICA
x russellianum syn. R. 'Russellianum'
russotinctum syn. R. alutaceum var. russotinctum
russotinctum var. of R. alutaceum var. of sp. in subsection TALIENSIA
'Ruth Lyons' clone of R. davidsonianum
rutilans var. of Azalea nudiflorum syn. R. periclymenoides
rutilans var. of Azalea periclymenoides syn. R. periclymenoides
ruttenii sp. in subgenus RHODODENDRON section VIREYA subsection SOLENOVIREYA
'Ryde Heron' ? clone of R. indicum

saavedranum syn. R. beyerinckianum
sabahense ssp. of R. durionifolium ssp. sp. in subgenus RHODODENDRON section VIREYA
saisiuense sp. in subgenus TSUTSUSI section TSUTSUSI
sakawanum syn. reticulatum
'Sakon' clone of R. kiusianum
salicifolium sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
salicifolium syn. R. multicolor
salicifolium var. of R. formosum syn. R. formosum var. formosum
salicinum var. of kwangsiense syn. R. mariae ssp. kwangtungense
salignum syn. R. lepidotum
x salmoneum syn. R. x kewense x campylocarpum
saluenense ssp. chameunum ssp. of sp. in subsection SALUENENSIA
saluenense ssp. saluenense clones
     'Exbury Saluenense'
saluenense ssp. saluenense ssp. of sp. in subsection SALUENENSIA
saluenense ssp. prostratum syn. saluenense ssp. chameunum
saluenense syn. R. saluenense ssp. saluenense
Saluenense (Series) syn. subsection SALUENENSIA
SALUENENSIA subsection of subgenus RHODODENDRON
sanctum sp. in subgenus TSUTSUSI section BRACHYCALYX
sanctum var. of R. weyrichii syn. R. sanctum
sanguineum ssp. aizoides syn. R. sanguineum ssp. sanguineum var. himertum
sanguineum ssp. atrorubrum syn. sanguineum ssp. sanguineum var. haemaleum
sanguineum ssp. cloiophorum syn. sanguineum ssp. sanguineum var. cloiophorum
sanguineum ssp. consanguineum syn. sanguineum ssp. sanguineum var. didymoides
sanguineum ssp. didymoides syn. sanguineum ssp. sanguineum var. didymoides
sanguineum ssp. didymum ssp. of sp. in subsection NERIIFLORA
sanguineum ssp. haemaleum syn. sanguineum ssp. sanguineum var. haemaleum
sanguineum ssp. himertum syn. sanguineum ssp. sanguineum var. himertum
sanguineum ssp. leucopetalum syn. sanguineum ssp. sanguineum var. cloiophorum
sanguineum ssp. melleum syn. sanguineum ssp. sanguineum var. himertum
sanguineum ssp. mesaeum syn. sanguineum ssp. sanguineum var. haemaleum
sanguineum ssp. roseotinctum syn. sanguineum ssp. sanguineum var. didymoides
sanguineum ssp. sanguineoides syn. sanguineum ssp. sanguineum var. sanguineum
sanguineum ssp. sanguineum var. cloiophorum var. of ssp. of sp. in subsection NERIIFLORA
sanguineum ssp. sanguineum var. didymoides var. of ssp. of sp. in subsection NERIIFLORA
sanguineum ssp. sanguineum var. haemaleum var. of ssp. of sp. in subsection NERIIFLORA
sanguineum ssp. sanguineum var. himertum var. of ssp. of sp. in subsection NERIIFLORA
sanguineum ssp. sanguineum var. haemaleum clones
     'James Comber'
     'Phantom Rock'
sanguineum ssp. sanguineum var. sanguineum var. of ssp. of sp. in subgenus NERIIFLORA
sanguineum var. didymoum syn. R. sanguineum ssp. didymum
sanguineum var. sanguinioides syn. R. sanguineum ssp. sanguineum var. sanguineum
sanguinioides. var of R. sanguineum syn. R. sanguineum ssp. sanguineum var. sanguineum
sanidoideum sp. in section AZALEASTRUM
santapaui sp. in subgenus RHODODENDRON section VIREYA subsection PSEUDOVIREYA
sarasinorum syn. R. javanicum ssp. schadenbergii
saravanense syn. R. lyi
sarcodes sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
sargentianum clones
     'Liz Ann'
     'Maricee'
     'Whitebait'
sargentianum sp. in section POGONANTHUM
saruwagedicum sp. in subgenus RHODODENDRON section VIREYA subsection PSEUDOVIREYA
saruwagedicum var. alpinum syn. R. saruwagedicum
sasakii syn. R. lasiostylum
sataense syn. R. kiusianum var. sataense
sataense var. of R. kiusianum var. of sp. in subgenus TSUTSUSI section TSUTSUSI
satsumense var. of R. dilatatum syn. R. decandrum
saxatile sp. in subgenus TSUTSUSI section TSUTSUSI
saxicolum sp. in subgenus TSUTSUSI section TSUTSUSI
saxifragoides sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
sayeri sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
scabridibracteum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
SCABRIFOLIA subsection in subgenus RHODODENDRON
scabrifolium syn. R. scabrifolium var. scabrifolium
scabrifolium var. pauciflorum var. of sp. in subsection SCABRIFOLIA
scabrifolium var. scabrifolium var. of sp. in subsection SCABRIFOLIA
scabrifolium var. spiciferum var. of sp. in subsection SCABRIFOLIA
scabrum f. linearisepalum syn. R. scabrum ssp. scabrum
scabrum ssp. amanoi ssp. of sp. in subgenus TSUTSUSI section TSUTSUSI
scabrum ssp. kaempferi syn. R. kaempferi
scabrum ssp. scabrum ssp. of sp. in subgenus TSUTSUSI section TSUTSUSI
scabrum var. kaempferi syn. R. kaempferi
scarlatinum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
'Scarlet Pimpernel' clone of R. forrestii ssp. papillatum
'Scarlet Runner' clone of R. forrestii ssp. papillatum
'Scarlet Salute' clone of R. x bakeri
schadenbergii syn. R. javanicum ssp. schadenbergii
schadenbergii syn. R. williamsii
schadenbergii var. of R. javanicum syn. javanicum ssp. schadenbergii
schistocalyx sp. in subsection PARISHIA
schizopeplum syn. R. aganniphum var. aganniphum
schizopeplum var. of R. aganniphum syn. R. aganniphum var. aganniphum
schizostigma sp. in subgenus RHODODENDRON section VIREYA subsection PSEUDOVIREYA
schlechteri sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
SCHLIPPENBACHII subseries of AZALEA series syn. partly of subgenus TSUTSUSI section BRACHYCALX
schlippenbachii f. albiflorum syn. R. schlippenbachii
schlippenbachii sp. in subgenus PENTANTHERA section SCIADORHODION
schoddei sp. in subgenus RHODODENDRON section VIREYA subsection PHAEOVIREYA
schulzei syn. R. beyerinckianum
SCIADORHODION (section) section in subgenus PENTANTHERA
SCIADORHODION subgen. of AZALEA series syn. subgenus PENTANTHERA section SCIADORHODION
sciaphilum syn. R. edgeworthii
scintillans syn. R. polycladum
'Scintillans Group' syn. R. polycladum
sclerocladum syn. R. cuneatum
scopulorum sp. in subsection MADDENIA
scortechinii sp. in subgenus RHODODENDRON section VIREYA subsection PSEUDOVIREYA
scottianum syn. R. pachypodum
scyphocalyx ssp. of R. dichroanthum ssp. of sp. in subsection NERIIFLORA
scyphocalyx syn. R. dichroanthum ssp. scyphocalyx
scyphocalyx var. of R. dichroanthum syn. R. dichroanthum ssp. scyphocalyx
scyphocalxy var. septentrionale syn. R. dichroanthum ssp. septentrionale
'S.D. Coleman' clone of R. prunifolium
'Seaboard' clone of R. atlanticum
searleanum sp. in subgenus RHODODENDRON section VIREYA subsection SOLENOVIREYA
searsiae sp. in subsection TRIFLORA
'Second Attempt' clone of R. callimorphum
seguini sp. in subsection TRIFLORA
seimundii sp. in subgenus RHODODENDRON section VIREYA subsection PSEUDOVIREYA
seinghkuense sp. in subsection EDGEWORTHIA
selebicum var. of R. quadrasianum var. of sp. in subgenus RHODODENDRON section VIREYA
selense ssp. axium syn. selense ssp. selense
selense ssp. chalarocladum syn. selense ssp. selense
selense ssp. dasycladum ssp. of sp. in subsection SELENSIA
selense ssp. dolerum syn. selense ssp. dasycladum
selense ssp. duseimatum syn. R. calvescens var. duseimatum
selense ssp. jucundum ssp. of sp. in subsection SELENSIA
selense ssp. metrium syn. selense ssp. selense
selense ssp. nanothamnum syn. selense ssp. selense
selense ssp. pagophilum syn. selense ssp. selense
selense ssp. probum syn. selense ssp. selense
selense ssp. selense ssp. of sp. in subsection SELENSIA
selense ssp. setiferum ssp. of sp. in subsection SELENSIA
SELENSE subseries of THOMSONII series syn. subsection SELENSIA
selense syn. R. selense ssp. selense
selense var. dasycladum syn. selense ssp. dasycladum
selense var. duseimatum syn. R. calvescens var. duseimatum
selense var. jucundum syn. selense ssp. jucundum
selense var. pagophilum syn. selense ssp. selense
selense var. probum syn. selense ssp. selense
SELENSIA (subsection) subsection in subgenus HYMENANTHES
semanteum syn. R. impeditum
SEMI-BARBATUM (series) syn. with subgenus MUMEAZALEA
semibarbatum only species in subgenus MUMEAZALEA
semilunatum syn. R. mekongense var. melinanthum
seminudum var. of R. giganteum syn. R. protistum var. protistum
semnoides sp. in subsection FALCONERA
semnum syn. R. praestans
sempervirens syn. R. ledebourii
simpervirens var. of dauricum syn. R. ledebourii
'Sempervirens Group' syn. R. dauricum
seniavinii sp. in subgenus TSUTSUSI section TSUTSUSI
seniavinii ? var. crassifolium var. of sp. in subgenus TSUTSUSI section TSUTSUSI
septentrionale ssp. of R. dichroanthum ssp. of sp. in subsection NERIIFLORA
septentrionale var. of dichroanthum syn. R. dichroanthum ssp. septentionale
septentrionale var. of R. scyphocalxy syn. R. dichroanthum ssp. septentrionale sequini
   syn. R. yunnanense
seranense syn. R. seranicum
seranicum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
'Serenade' clone of R. davidsonianum
seriocalyx syn. R. saluenense ssp. chameunum
serotinum sp. in subsection FORTUNEA
serpens syn. R. erastum
serpyllifolium syn. R. nakaharai
serpyllifolium f. album syn. R. serpyllifolium
serpyllifolium clones
     'Albiflorum'
serpyllifolium sp. in subgenus TSUTSUSI section TSUTSUSI
serpyllifolium var. albiflorum syn. R. serpyllifolium
serrulatum f. molliculum syn. R. viscosum
serrulatum syn. R. viscosum
serrulatum var. georgianum syn. R. viscosum
serrulatum var. of R. sieboldii syn. R. indicum
serrulatum var. of R. viscosum syn. R. viscosum
'Sesame' clone of R. pachytrichum
sessilifolium sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
x sesterianum syn. R. 'Sesterianum'
setaceum var. of R. mitriforme var. of sp. in section CHONIASTRUM
setiferum syn. R. selense ssp. setiferum
setiferum ssp. of R. selense ssp. of sp. in subsection SELENSIA
setistylum var of R. meridionale syn. R. meridionale var. meridionale
'Setosa' clone of R. lapponicum
setosum sp. in subsection LAPPONICA
'Seven Devils' clone of R. macrophyllum
'Seventh Heaven' A.M. 1978 clone of R. sutchuenense
x seymourii syn. R. canadense x luteum(as R. flavum)
shaanxiense sp. in subsection TRIFLORA
shanii sp. in subsection TALIENSIA
x sheilae syn. R. abiietifolium x busifolium
sheilae syn T. x sheilae
sheltonii syn. R. vernicosum
shensiense syn. R. oreodoxa var. shensiense
shensiense var. of R. oreodoxa var. of sp. in subsection FORTUNEA
shepherdii syn. R. kendrichii
sherriffii sp. in subsection THOMSONIA
shikokianum syn. R. weyrichii
shimenense sp. in subsection ARGYROPHYLLA
shimianense sp. in subsection TRIFLORA
shimidzuanum syn. kiyosumense
shiwandashnense sp. in section CHONIASTRUM
skikokianum var. of R. pentaphyllum syn. R. pentaphyllum
'Shogetsu' clone of R. kiusianum
shojoense syn. R. mariesii
shweliense sp. in subsection GLAUCA
siamensis syn. R. moulmainense
sichotense sp. in subsection RHODORASTRA
sichotense ssp. of dauricum syn. R. sichotense
x sicuicolum syn. R. x silvicolum
sidereum clones
     'Glen Rosa'
sidereum sp. in subsection GRANDIA
siderophylloides syn. R. oreotrephes
siderophyllum sp. in subsection TRIFLORA
'Sidlaw' P.C. 1969 clone of R. vernicosum
sieboldii syn. R. kaempferi
sieboldii var. serrulatum syn. R. indicum
sigillatum syn. R. phaeochrysum var. levistratum
sikangense var. exquisitum var. of sp. in subsection MACULIFERA
sikangense var. sikangense var. of sp. in subsection MACULIFERA
sikayotaisanense sp. in subgenus TSUTSUSI subsection TSUTSUSI
x sikidera syn. R. indicum x kaempferi
x sikkimense syn. R. thomsonii x (probably R. arboreum)
silvaticum syn. R. lanigerum
silvaticum var. of R. lanigerum syn. R. lanigerum
'Silvia' A.M. 1953, F.C.C. clone of R. lanigerum
x silvicolum syn. R. cuneifolium x ericoides
silvicolum var. of R. ericoides syn R. x silvicolum
simiarum ssp. youngae syn. R. adenopodum
simiarum syn. R. adenopodum
simiarum var. deltoideum var. of sp. in subsection ARGYROPHYLLA
simiarum var. simiarum var. of sp. in subsection ARGYROPHYLLA
simiarum var. versicolor var. of sp. in subsection ARGYROPHYLLA
simsii var. albiflorum var. of sp. in subgenus TSUTSUSI section TSUTSUSI
simsii var. mesembrinum var. of sp. in subgenus TSUTSUSI section TSUTSUSI
simsii var. of R. indicum syn. R. simsii var. simsii
simsii clones
     'Gumpo Fancy'
     'Gumpo Pink'
     'Gumpo Red'
     'Gumpo White'
simsii var. simsii var. of sp. in subgenus TSUTSUSI section TSUTSUSI
simsii var. yakuinsulare syn. R. scabrum ssp. scabrum
simulans sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
simulans syn. R. mimetes var. simulans
simulans var. of R. mimetes var. of sp. in subsection TALIENSIA
sinense syn. R. molle ssp. japonicum
sinense var. of R. indicum syn. R. scabrum ssp. scabrum
sinense var. rosea syn. R. molle ssp. japonicum
sinense var. of Azalea pontica syn. R. molle ssp. japonicum
SINENSES section of RHODODENDRON syn. SINENSIA
SINENSIA subsection in subgenus PENTANTHERA section PENANTHERA
sinofalconeri sp. in subsection FALCONERA
sinogrande sp. in subsection GRANDIA
sinolepidotum syn. R. lepidotum
sinonuttallii syn. R. nuttallii
sino-vaccinioides syn. R. virgatum
sinovirgatum syn. R. virgatum ssp. oleifolium
SIPHONOVIREYA subsection in section VIREYA
'Sir Charles Butler' clone of R. fortunei ssp. fortunei
'Sir Charles Lemon' ? clone of R. arboreum ssp. cinnamomeum
'Sleea' P.C. 1964 clone of R. martinianum
sleumeri syn. R. blackii
smilesii syn. R. veitchianum
smirnowii sp. in subsection PONTICA
smithii clones
     'Fleurie'
smithii syn. R. argipeplum
smithii var. of R. indicum syn. R. pulchrum
x smithii syn. R. ponticum x arboreum
'Smoky Mountaineer' clone of R. calendulaceum
x sochadzeae syn. (R. ponticum x R. caucasicum)
SOLENOVIREYA subsection in section VIREYA
solitarium sp. in subgenus RHODODENDRON section VIREYA subsection PHAEOVIREYA
sonomense syn. R. occidentale
sonomense var. of R. occidentale syn. R. occidentale
sordidum syn. R. pruniflorum
sororium sp. in subgenus RHODODENDRON section VIREYA subsection PSEUDOVIREYA
SOULIEA (subsection) syn. subsection CAMPYLOCARPA
souliei clones
     'Elsa Reid'
     'Exbury Pink'
     'Windsor Park'
souliei sp. in subsection CAMPYLOCARPA
spadiceum syn. R. rufulum
spanothrichum sp. in subsection IRRORATA
sparsiflorum syn. R. camelliiflorum
sparsifolium sp. in subgenus TSUTSUSI section TSUTSUSI
spathulatum sp. in subgenus RHODODENDRON section VIREYA subsection PSEUDOVIREYA
'Spatter Paint' clone of R. irroratum ssp. irroratum
speciosum f. of quinquefolium syn. R. quinquefolium
speciosum syn. R. ponticum
speciosum syn. R. calendulaceum
speciosum var. major syn. R. calendulaceum
spectabile syn. R. javanicum ssp. schadenbergii
sperabile syn. R. sperabile var. sperabile
sperabile var. sperabile var. of sp. in subsection NERIIFLORA
sperabile var. weihsiense var. of sp. in subsection NERIIFLORA
sperabiloides sp. in subsection NERIIFLORA
sphaeranthum syn. R. trichostomum
sphaeroblastum var. sphaeroblastum var. of sp. in subsection TALIENSIA
sphaeroblastum var. wumengense var. of sp. in subsection TALIENSIA
spiciferum syn. R. scabrifolium var. spiciferum
spiciferum var. album (unresolved)
spiciferum var. of R. scabrifolium var. of sp. in subsection SCABRIFOLIA
spilanthum syn. R. thymifolium
spilotum sp. in subsection GLISCHRA
spinigerum syn. R. chrysocalyx
spinuliferum var. glabrescens var. of sp. in subsection SCABRIFOLIA
spinuliferum clones
     'Blackwater'
     'Jack Hext'
spinuliferum var. spinuliferum var. of sp. in subsection SCABRIFOLIA
x spinulosum syn. R. 'Sinulosum' grex 'Spinulosum'
splendens (unplaced)
spodopeplum syn. R. tephropeplum
spomtaneum f. of degronianum syn. R. degronianum ssp. degronianum
spondylophyllum sp. in section VIREYA subsection PHAEOVIREYA
spooneri syn. R. decorum
'Spring Party' clone of R. vaseyi
'Spring Sonnet' A.M. 1976 clone of R. vernicosum
squarrosum syn. R. rubiginosum
stamineum var. lasiocarpum var. of sp. in section CHONIASTRUM
stamineum var. stamineum var. of sp. in section CHONIASTRUM
x standishii syn. R. 'Standishi'
stapfianum sp. in subgenus RHODODENDRON section VIREYA subsection SOLENOVIREYA
'Star Trek' clone of R. davidsonianum
stelligerum sp. in subgenus RHODODENDRON section VIREYA subsection PHAEOVIREYA
stenaulum syn. R. moulmainense
stenopetalum sp. in subgenus TSUTSUSI subsection TSUTSUSI
stenophyllum ssp. angustifolium ssp. of sp. in subgenus RHODODENDRON section VIREYA
   subsection VIREYA
stenophyllum ssp. stenophyllum ssp. of sp. in subgenus RHODODENDRON section VIREYA
   subsection VIREYA
stenophyllum var. angustifolum var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection VIREYA
stenophyllum syn. R. makinoi
stenoplastum syn. R. rubiginosum
stereophyllum syn. R. tatsienense var. tatsienense
stevensianum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
stewartianum sp. in subsection THOMSONIA
stewartianum var. aiolosalpinx syn. R. stewartianum
stewartianum var. tantulum syn. R. stewartianum
stictophyllum syn. R. nivale ssp. boreale
stolleanum sp. in subgenus RHODODENDRON section VIREYA subsection PHAEOVIREYA
'Stonehurst' A.M. 1961 clone of R. lanigerum
stonori syn. R. commonae
stresemannii sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
strictum var. of R. alpicola syn. R. nivale ssp. boreale
strigillosum sp. in subsection MACULIFERA
strigillosum var. monosematum syn. R. monosematum
suaveolens sp. in subgenus RHODODENDRON section VIREYA subsection SOLENOVIREYA
suaveolens f. roseum f. of sp. in subgenus RHODODENDRON section VIREYA subsection SOLENOVIREYA
stylotrichum var. of R. dielsianum var. of sp. in subgenus RHODODENDRON section VIREYA
subansiriense sp. in subsection THOMSONIA
subarcticum syn. R. tomentosum var. subarcticum
subarcticum var. of R. tomentosum var. of sp. in subgenus RHODODENDRON section RHODODENDRON
   subsection LEDUM
subcerinum sp. in subgenus TSUTSUSI subsection TSUTSUSI
subcoombense syn. R. concinnum
subcordatum syn. R. longiflorum var. subcordatum
subcordatum var. of R. longiflorum var. of sp. in subgenus RHODODENDRON section VIREYA
subcrenulatum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
subenerve sp. in subgenus TSUTSUSI subsection TSUTSUSI
subenerve var. nudistylum syn. R. tsoi
suberosum syn. R. yunnanense
subestipitatum sp. in subgenus AZALEASTRUM section CHONIASTRUM
subfalcatum var. of R. kwangsiense syn. R. mariae ssp. kwangtungense
subflumineum sp. in subgenus TSUTSUSI subsection TSUTSUSI
subglabra f. of augustinii syn. R. augustinii ssp. chasmanthum
subglabrum f. of R. canescens syn. R. canescens
sublanceolatum syn. R. scabrum ssp. scabrum
sublanceolatum var. of R. indicum syn. R. scabrum ssp. scabrum
sublateritium syn. R. scabrum ssp. scabrum
subnikomontanum syn. R. keiskei
subpacificum syn. R. loranthiflorum
subpilosum var. of R. aperantum syn. R. aperantum
subsessile sp. subgenus TSUTSUSI in section TSUTSUSI
subspathulatum var. of R. cuneifoium syn. R. borneense ssp. villosum
subspathulatum var. of R. cuneifolium syn. R. bogobonum
subuliferum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
subulosum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
succothii sp. in subsection BARBATA
sulfureum sp. in subsection BOOTHIA
sulphureum syn. sulfureum
sumatranum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
'Summer Skies' clone of R. augustinii ssp. augustinii
'Summer Sunset' clone of R. prunifolium
'Summertime' A.M. 1974 clone of R. maximum
'Sunningdale' A.G.M. 1925 clone of R. hippophaeoides var. hippophaeoides
'Sunte Rock' P.C. 1969 clone of R. praestans
'Sunte Rose' clone of R. x geraldii
'Superbum' clone of R. degronianum ssp. degronianum
superbum sp. in subgenus RHODODENDRON section VIREYA subsection PHAEOVIREYA
supranubium syn. R. pachypodum
surasianum sp. in subsection MADDENIA
surugaense syn. R. tosaense
sutchuenense clones
     'Seventh Heaven'
sutchuenense sp. in subsection FORTUNEA
sutchuenense var. geraldii syn. R. x geraldii
'Suva' clone of R. vaseyi
'Sweet Bay' A.M. 1960 clone of R. trichostomum
'Swinhoe' A.M. 1963 clone of R. floribundum
sycnanthum syn. R. rigidum
syncollum syn. R. phaeochrysum var. agglutinatum
syringoideum sp. in subgenus RHODODENDRON section VIREYA subsection SOLENOVIREYA

taggianum clones
     'Deì James'
taggianum sp. in subsection MADDENIA
taibaiense sp. in subgenus RHODODENDRON subsection LAPPONICA
taiense sp. in subgenus AZALEASTRUM section CHONIASTRUM
'Taisenhaku' clone of R. kiusianum
taipaoense sp. in subgensu TSUTSUSI section TSUTSUSI
taishunense sp. in subgenus AZALEASTRUM section CHONIASTRUM
taitunense var. of R. pseudochrysanthum ssp. morii var. of ssp. of sp. in subsection
   MACULIFERA or syn. R. morii var. taitunense.
'Taiping' clone of R. triflorum
'Takochiko' clone of R. kiusianum
TALIENSE (series) syn. subsection TALIENSIA
taiwanalpinum sp. subgenus TSUTSUSI in section TSUTSUSI
taiwanianum syn. R. kawakamii
x takanashianum syn. R. reticulatum x tashiroi
taliense sp. in subsection TALIENSIA
TALIENSIA (subsection) subsection in subgenus HYMENANTHES
tamaense syn. R. cinnabarinum ssp. tamaense
tamaense ssp. of R. cinnabarinum ssp. of sp. in subsection CINNABARINA
tamurae syn. R. eriocarpum
tamurae var. of R. indicum syn. R. eriocarpum
tanakae syn. R. tsusiophyllum
tanakae syn. R. tsusiophyllum
tanakai syn. R. moulmainense
tanastylum syn. R. tanastylum var. tanastylum
tanastylum var. lingzhiense var. of sp. in subsection IRRORATA
tanastylum var. pennivenium var. of sp. in subsection IRRORATA
tanastylum var. tanastylum var. of sp. in subsection IRRORATA
tantulum var. of R. stewartianum syn. R. stewartianum
tapeinum syn. R. megeratum
tapelouense syn. R. tatsienense
tapetiforme sp. in subsection LAPPONICA
taquetii syn. R. mucronulatum
taronense syn. R. dendricola
'Taronense Group' syn. R. dendricola
tashiroi clones
     'Numazu'
tashiroi sp. in subgenus TSUTSUSI section TSUTSUSI
TASHIROIA(subsection) syn. section TSUTSUSI
tatsienense var. nudatum var. of sp. in subsection TRIFLORA
tatsienense var. tatsienense var. of sp. in subsection TRIFLORA
'Tatsuta' clone of R. kiusianum
x tatuoi syn R. dilatatum x wadanum
tawadae syn. R. eriocarpum
tawadae var. of R. eriocarpum syn. R. eriocarpum
tawangense syn. R. neriiflorum ssp. phaedropum
taxifolium sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
taxoides sp. in subgenus RHODODENDRON section VIREYA subsection PSEUDOVIREYA
taylori syn. R. 'Taylorii'
tebotan syn. R. pulchrum
tectum syn. R. x transiens
tectum var. purpureum syn. x komatsui
telmateium sp. in subsection LAPPONICA
telopeum syn. R. campylocarpum ssp. caloxanthum
'Telopeum Group' syn. R. campylocarpum ssp. caloxanthum
telopeum ssp. of R. campylocarpum syn. R. campylocarpum ssp. caloxanthum
temenium ssp. albipetalum syn. R. eudoxum var. eudoxum
temenium ssp. chrysanthum syn. R. temenium var. gilvum
temenium ssp. dealbatum syn. R. temenium var. dealbatum
temenium ssp. glivum syn. R. temenium var. gilvum
temenium ssp. glaphyrum syn. R. temenium var. dealbatum
temenium ssp. of R. eudoxum syn. R. temenium var. temenium
temenium ssp. pothinum syn. R. temenium var. temenium
temenium ssp. rhodanthum syn. R. eudoxum var. eudoxum
temenium var. dealbatum var. of sp. in subsection NERIIFLORA
temenium var. gilvum clones
     'Cruachan'
temenium var. gilvum var. of sp. in subsection NERIIFLORA
temenium var. of temenium var. of sp. in subsection NERIIFLORA
temoense var. of R. laudandum var. of sp. in section POGONANTHUM
'Tenshi' clone of R. kiusianum
tenue syn. R. fuchsiifolium
tenuifolium sp. in subsection CINNABARINA
tenuilaminare sp. in subgenus TSUTSUSI subsection TSUTSUSI
tenuistylosum var. of R. pachytrichum var. of sp. in subsection MACULIFERA
TEPHROPEPLA subsection in subgenus RHODODENDRON
TEPHROPEPLUM (Subseries) syn. mostly with subsection TEPHROPEPLA
tephropeplum clones
     'Butcher Wood'
tephropeplum sp. in subsection TEPHROPEPLA
tetramerum f. of var. typicum of R. tschonoskii syn. R. tschonoskii var. tschonoskii
tetramerum syn. R. tschonoskii var. tschonoskii
tetramerum f. of R. toschonoskii syn. R. tschonoskii var. tschonoskii
tetramerum var. of R. txchonoskii syn. R. tschonoskii var. tschonoskii
teysmannii syn. R. robinsonii
teysmannii syn. R. javanicum var. teysmannii
thaumasianthum sp. in subgenus RHODODENDRON section VIREYA subsection PHAEOVIREYA
thayerianum sp. in subsection ARGYROPHYLLA
'The Bride' F.C.C. 1971 ? clone of white R. caucasicum
theiochroum syn. R. sulfureum
theiophyllum syn. R. phaeochrysum var. levistratum
THERORHODION (subgenus) subgenus in genus RHODODENDRON
Therorhodion camtschaticum syn. R. camtschaticum
thibaudense syn. R. cinnabarinum
'Thimble' A.M. 1966 clone of R. campylogynum
THOMSONIA (subsection) subsection in subgenus HYMENANTHES
thomsonii ssp. candelabrum syn. R. x candelabrum
thomsonii ssp. lopsangianum ssp. of sp. subsec. THOMSONIA
thomsonii ssp. thomsonii ssp. of sp. in subsection THOMSONIA
thomsonii syn. R. thomsonii ssp. thomsonii
thomsonii var. candelabrum syn. R. x candelabrum
thomsonii var. cyanocarpum syn. R. cyanocarpum
thomsonii var. lapsangianum syn. R. thomsonii ssp. lopsangianum
thomsonii var. pallidum syn. R. x candelabrum
THOMSONII subseries of THOMSONII series syn. partly subsection THOMSONIA
thunbergii syn. R. obtusum
thymifolium sp. in subsection LAPPONICA
thyodocum syn. R. baileyi
tianlinense sp. in subgenus AZALEASTRUM section AZALEASTRUM
tigerstedtii ssp. of R. brachycarpum syn. R. brachycarpum ssp. barchycarpum
tigrinum var. of R. purpureum syn. R. maximum
timeteum syn. R. oreotrephes
tingwuense syn. R. tsoi
tokushimense var. of R. lagopus var. of sp. in subgenus TSUTSUSI section BRACHYCALYX
tokushimense var. of R. nudipes ssp. nudipes syn. R. lagopus var. tokushimense
tolmachevii sp. in subgenus RHODODENDRON section RHODODENDRON subsection LEDUM
tomentosum var. subarcticum var. of sp. in subgenus RHODODENDRON section RHODODENDRON
   subsection LEDUM
tomentosum var. tomentosum var. of sp. in subgenus RHODODENDRON section RHODODENDRON
   subsection LEDUM
tomentosum var. of R. viscosum syn. R. viscosum
'Tom Spring Smythe' A.M. 1974 clone of R. dalhousiae var. dalhousiae
'Tony Schilling' A.M. 1974, F.C.C. 1974 clone of R. arboreum ssp. cinnamomeum var. roseum
x torlonianum syn. R. 'Torlonianum'
torquatum syn. R. dichroanthum ssp. scyphocalyx
torricellense syn. R. macgregoriae var. glabifilium
tosaense clones
     'Ralph Clarke'
tosaense sp. in subgenus TSUTSUSI section TSUTSUSI
tosaense var. of R. obtusum syn. R. tosaense
tovernae syn. R. konori var. konori
'Tower Court Augustinii' clone of R. augustinii ssp. augustinii
toxopei sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
TRACHYRHODION see PSEUDORHODORASTRUM
traillianum syn. R. traillianum var. traillianum
traillianum var. dictyotum clones
     'Kathmandu'
traillianum var. dictyotum var. of sp. in subsection TALIENSIA
traillianum var. traillianum var. of sp. in subsection TALIENSIA
x transiens syn. R. kaempferi x macrosepalum
'Triangle' P.C. 1978 clone of R. cinnabarinum ssp. tamaense
trichanthum clones
     'Honey Wood'
trichanthum sp. in subsection TRIFLORA
trichanthum syn. R. pseudotrichantum
trichanthum var. of microphyton syn. R. microphyton
trichocalyx syn. R. keiskei
TRICHOCLADA (subsection) subsection in subgenus RHODODENDRON
TRICHOCLADUM (series) syn. subsection TRICHOCLADA
trichocladum var. longipilosum var. of sp. in subsection TRICHOCLADA
trichocladum var. nepalense syn. R. mekongense var. mekongense
trichocladum var. trichocladum var. of sp. in subsection TRICHOCLADA
trichomiscum syn. R. eudoxum var. eudoxum
trichomiscum ssp. of R. eudoxum syn. R. eudoxum var. eudoxum
trichophlebium syn. R. eudoxum var. eudoxum
trichoplebium ssp. of R. fulvastum syn. R. eudoxum var. eudoxum
x trichophorum syn. R. trichanthum x R. augustinii
trichopodum syn. R. oreotrephes
trichostomum clones
     'Collingwood Ingram'
     'Lakeside'
     'Quarry Wood'
     'Rae Berry'
     'Sweet Bay'
trichostomum sp. in section POGONANTHUM
trichostomum var. hedyosmum syn. R. hedyosmum
trichostomum var. ledoides syn. R. trichostomum
trichostomum var. radinum syn R. trichostomum
trichostylum var. of R. retusum var. of sp. in subgenus RHODODENDRON section VIREYA
x tricolor is invalid
TRIFLORA subsection in subgenus RHODODENDRON
TRIFLORUM (series) syn. partly with subsection AFGANICA
TRIFLORUM (series) syn. partly subsections TEPHROPEPLA & TRIFLORA
triflorum ssp. multiflorum ssp. of sp. in subsection TRIFLORA
triflorum ssp. triflorum clones
     'Taiping'
triflorum ssp. triflorum ssp. of sp. in subsection TRIFLORA
triflorum var. bauhiniflorum is invalid
triflorum var. mahogoni syn. triflorum ssp. triflorum
triflorum syn. R. triflorum ssp. triflorum
trilectorum sp. in subsection NERIIFLORA
trimoense var. of R. tsariense var. of sp. in subsection LANATA
trinerve syn. R. tschonoskii var. trinerve
trinerve var. of R. tschonoskii var. of sp. in subgenus TSUTSUSI section TSUTSUSI
triplonaevium syn. R. alutaceum var. russotinctum
tritifolium syn. R. alutaceum var. russotinctum
triumphans sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
truncatulatum ssp. of erythrocalyx syn. R. x erythrocalyx
truncicolum sp. in subgenus RHODODENDRON section VIREYA subsection PHAEOVIREYA
tsaii sp. in subsection LAPPONICA
tsangpoense syn. R. charitopes ssp. tsangpoense
tsangpoense ssp. of R. charitopes ssp. of sp. in subsection GLAUCA
tsangpoense var. curvistylum syn. R. charitopes ssp. tsangopoense
tsangpoense var. pruniflorum syn. R. pruniflorum
tsariense var. magnum var. of sp. in subsection LANATA
tsariense var. trimoense var. of sp. in subsection LANATA
tsariense var. tsariense clones
     'Yum-Yum'
tsariense var. tsariense var. of sp. in subsection LANATA
tsarongense syn. R. primuliflorum
tschonoskii f. tetramerum syn. R. tschonoskii var. tschonoskii
tschonoskii var. tetramerum syn. R. tschonoskii var. tschonoskii
tschonoskii var. trinerve var. of sp. in subgenus TSUTSUSI section TSUTSUSI
tschonoskii var. tschonoskii var. of sp. in subgenus TSUTSUSI section TSUTSUSI
tsinlingense sp. in subsection TEPHROPEPLA
tsoi sp. in subgenus TSUTSUSI section TSUTSUSI
'Tsukushikomachi' clone of R. kiusianum
tsurugisanense var. nudipetiolatum var. of sp. in section BRACHYCALYX
tsurugisanense var. of ssp. niphophilum of sp. nudipes syn. R. tsurugisanense var.
   tsurugisanense
tsurugisanense var. tsurgisanense var. of sp. in section BRACHYCALYX
'Tsurumi' clone of R. kiusianum
tsusiophyllum sp. in subgenus TSUTSUSI subsection TSUTSUSI
TSUSUIOPHYLLUM(genus) syn. subgen TSUTSUSI section TSUTSUSI
Tsusuiophyllum tanakae syn. R. tsusiophyllum
TSUSIOPSIS (section) now included in section TSUTSUSI
TSUTSUSI (section) section in subgenus TSUTSUSI
TSUTSUSI (subgenus) subgenus in genus RHODODENDRON
tuba sp. in subgenus RHODODENDRON section VIREYA subsection SOLENOVIREYA
tuberculiferum sp. in subgenus RHODODENDRON section VIREYA subsection PHAEOVIREYA
tubidorum var. of kaempheri syn. R. kaempheri
'Tubiflorum' clone of R. kaempferi
tubiflorum syn. malayanum var. malayanum
tubiflorum syn. R. longiflorum var. longiflorum
tubiflorum syn. R. zollingeri
tubiflorum var. of R. javanicum syn. R. longiflorum var. longiflorum
tubiforme var. of R. glaucophyllum syn . R. glaucophyllum ssp. tubiforme
tubulosum sp. in subgenus RHODODENDRON section POGONANTHUM
tumescens var. of R. forrestii syn. R. forrestii var. papillatum
   or (R. papillatum x R. chamaethomsonii)
tutcherae var. gymnocarpum var. of sp. in section CHONIASTRUM
tutcherae var. tutcherae var. of sp. in section CHONIASTRUM
typicum var. (f. tetramerum) of R. tschonoskii syn. R. tschonoskii var. tschonoskii

uliginosum syn. R. laetum
ultimum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
umbelliferum syn. R. mariesii
unciferum sp. in section TSUTSUSI
undulatum syn. R. arboreum
ungernii sp. in subsection PONTICA
'Unicolor' clone of R. keysii
unicolor var. of R. keysii syn. R. keysii
unciferum sp. in subgenus TSUTSUSI subsection TSUTSUSI
UNIFLORA subsection of subgenus RHODODENDRON
UNIFLORUM (series) syn. subsection UNIFLORA
uniflorum syn. R. uniflorum var. uniflorum
uniflorum var. imperator clones
     'Purple Emperor'
uniflorum var. imperator var. of sp. in subsection UNIFLORA
uniflorum var. uniflorum clones
     'Dalkeith'
uniflorum var. uniflorum var. of sp. in subsection UNIFLORA
'Unzensakura' clone of R. kiusianum
'Ukon' clone of R. kiusianum
urophyllum sp. in section PARISHIA
uvarifolium var. griseum var. of sp. in subection FULVA
uvarifolium var. uvarifolium clones
     'Reginald Childs'
     'Yangtze Bend'
uvarifolium var. uvarifolium var. of sp. in subsection FULVA
uwaense sp. in section AZALEASTRUM

vaccinioides sp. in subgenus RHODODENDRON section VIREYA subsection PSEUDOVIREYA
valentinianum var. changii syn. R. changii
valentinianum var. oblongifolium var. of sp. in subsection MADDENIA
valentinianum var. valentinianum clones
     'Aola'
valentinianum var. valentinianum var. of sp. in subsection MADDENIA
vanderbiltianum sp. in subgenus RHODODENDRON section VIREYA subsection PSEUDOVIREYA
vandeursenii syn. R. vitis-idea
x vanhoeffeni syn. R. lapponicum x R. tomentosum var. tomentosum
vaniotii syn. R. esquirolii
vanvuurenii sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
'Variegatum' clone R. ponticum
'Variegatum' clone of R. ferrugineum
variegatum f. of degronianum syn. R. degronianum ssp. degronianum
variolosum var. andersonii var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection MALAYOVIREYA
variolosum var. variolosum var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection MALAYOVIREYA
vaseyi f. album syn. R. vaseyi
vaseyi clones
     'Spring Party'
     'Suva'
     'White Find'
vaseyi sp. in subgen. PENTHANTHERA section RHODORA
vaseyi var. album syn. R. vaseyi
veitchianum clones
     'Ashcombe'
     'Margaret Mead'
veitchianum sp. in subsection MADDENIA
vellereum syn. R. principis
vellereum var. of R. principis syn. R. principis
'Vellereum Group' syn. R. principis
velutinum f. of R. verticillatum f. of sp. in subgenus RHODODENDRON section VIREYA
velutinum syn. verticillatum f. velutinum
venator only species in subsection VENATORA
VENATORA (subsection) subsection in subgenus HYMENANTHES
venosum sp. in section PONTICUM unplaced
venustrum syn. R. viscosum
venustum syn. R. periclymenoides
vernicosum clones
     'Gary Herbert'
     'Kulu'
     'Loch Eck'
     'Mount Siga'
     'Sidlaw'
     'Spring Sonnet'
vernicosum sp. in subsection FORTUNEA
verruciferum sp. in subsection FORTUNEA
x verruculosum syn. R. x flavidum
VERTICILLATAE (section) syn. section BRACHYCALYX
versicolor syn. R. simiarum var. versicolor
versicolor var. of R. simiarum var. sp. in subsection ARGYROPHYLLA
versteegii sp. in subgenus RHODODENDRON section VIREYA subsection ALBOVIREYA
verticillatum syn. R. jasminiflorum var. oblongifolium
verticillatum syn. R. radians var. minahasae
verticillatum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
verticillatum syn. R. vidalii
verticillatum f. velutinum f. of sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
vesiculiferum clones
     'High Flier'
vesiculiferum sp. in subsection GLISCHRA
vestitum syn. R. selense ssp. setiferum
vialii sp. in section AZALEASTRUM
viburnifolium syn. R. simsii var. simsii
vicarium syn.R. nivale ssp. boreale
vicinum syn. R. phaeochrysum var. levistratum
x victorianum syn. R. 'Victorianum'
vidalii sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
villosulum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
villosum ssp. of R. borneese sp. in subgenus RHODODENDRON section VIREYA
villosum syn. R. trichanthum
villosum unplaced
villosum var. of R. quadrasianum syn. R. borneese ssp. villosum
vilmorinianum syn. R. augustinii ssp. augustinii
vinicolor sp. in subgenus RHODODENDRON section VIREYA subsection MALAYOVIREYA
vinkii sp. in subgenus RHODODENDRON section VIREYA subsection PSEUDOVIREYA
'Vin Rose' A.M. 1953 clone of R. cinnabarinum ssp. cinnabarinum
violaceum syn. R. nivale ssp. boreale
'Violet Cloud' ? clone of R. pulchrum (? hybrid)
virens var. of Azalea viscosa syn. R. viscosum
VIREYA section of subgenus RHODODENDRON
VIREYA subsection of section VIREYA in subgenus RHODODENDRON
VIRGATA (subsection) subsection of subgenus RHODODENDRON
VIRGATUM (series) syn. in the most part with subsection VIRGATA
virgatum syn. R. virgatum ssp. virgatum
virgatum ssp. virgatum ssp. of sp. in subsection VIRGATA
virgatum ssp. oleifolium ssp. of sp. in subsection VIRGATA
virgatum var. glabriflorum var. of sp. in subsection VIRGATA
'Virgin' clone of white R. catawbiense
viridescens sp. in subsection TRICHOCLADA
viridifolium f. of canadense syn. R. canadense
viscidifolium sp. in subsection THOMSONIA
VISCIDULA (section) section in subgenus PENTANTHERA
viscidum sp. in subgenus TSUTSUSI subsection TSUTSUSI
viscigemmatum sp. in subgenus TSUTSUSI subsection TSUTSUSI
viscistylum sp. in subgenus TSUTSUSI section BRACHYCALYX
viscistylum var. amakusaense syn. amakusaense
viscistylum var. glaucum syn. osuzuyamense
viscistylum var. hyugaense syn. hyugaense
viscistylum var. of R. decandrum syn. R. viscistylum
viscosum f. coerulescens syn. R. viscosum
viscosum f. glaucum syn. R. viscosum
viscosum f. hispidum syn. R. viscosum
viscosum f. rhodantha syn. R. viscosum
viscosum f. roseum syn. R. viscosum
viscosum f. rubescens syn. R. viscosum
viscosum sp. in subgenus PENTANTHERA section PENTANTHERA
viscosum var. aemulans syn. R. viscosum
viscosum var. glaucum syn. R. viscosum
viscosum var. hispidum syn. R. viscosum
viscosum var. montanum syn. R. viscosum
viscosum var. nitidum syn. R. viscosum
viscosum var. rubescens syn. R. viscosum
viscosum var. serrulatum syn. R. viscosum
viscosum var. tomentosum syn. R. viscosum
vitis-idaea sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
vittatum syn. R. 'Vittatum'
vittatum var. punctatum syn. R. 'Vittatum'

wadanum sp. in subgenus TSUTSUSI section BRACHYCALYX
wadanum var. lagopus syn. R. lagopus var. logopus
wadanum var. leucanthum syn. R. wadanum
wadanum var. of reticulatum syn. R. wadanum
'Wakehurst' A.M. 1975 clone of R. rubiginosum
wallaceanum sp. in section PONTICUM unplaced
wallichii sp. in subsection CAMPANULATA
walongense sp. in subsection MADDENIA
'Walter Maynard' A.M. 1975 clone of R. ciliicalyx
'War Paint' clone of R. elliottii
'Ward's Rex' clone of R. rex ssp. rex
wardii syn. R. wardii var. wardii
wardii var. puralbum var. of sp. in subsection CAMPYLOCARPA
wardii var. wardii clones
     'Campbell's Strain'
     'Ceramic'
     'Ellestee'
     'Star Trek'
wardii var. wardii var. of sp. in subsection CAMPYLOCARPA
warianum syn. R. leptanthum var. warianum
warianum var. of R. leptanthum var. of sp. in subgenus RHODODENDRON section VIREYA
warrenii syn. R. albiflorum var. warrenii
warrenii var. of R. albiflorum var. of sp. in subgenus CANDIDASTRUM
washingtonianum syn. R. macrophyllum
wasonii var. wasonii clones
     'Rhododactylum'
wasonii var. wasonii var. of sp. in subsection TALIENSIA
wasonii var. wenchuanense var. of sp. in subsection TALIENSIA
watsonii sp. in subsection GRANDIA
wattii sp. in subsection GRANDIA
'Waxen Bell' A.M. 1965 clone of campanulatum ssp. campanulatum
websteranum var. websteranum var. of sp. in subsection LAPPONICA
websteranum var. yulongense var. of sp. in subsection LAPPONICA
weihsiense var. of R. sperabile var. of sp. in subsection NERIIFLORA
weldianum syn. R. rufum
x welsianum syn. R. arboreum x ?
wenchuanense var. of R. wasonii var. of sp. in subsection TALIENSIA
wentianum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
'Westhaven' clone of aberconwayi
westlandii syn. R. moulmainense
weyrichii sp. in section subgenus TSUTSUSI section BRACHYCALYX
weyrichii var. amagianum syn. amagianum
weyrichii var. sanctum syn. sanctum
'Whalley's Augustinii' clone of augustinii ssp. augustinii
'White Brightness' clone of mucronulatum
'White Find' clone of vaseyi
whiteheadii sp. in subgenus RHODODENDRON section VIREYA
'White Lace' A.M. 1974 clone of racemosum
'White Plains' clone of alutaceum var. iodes
'White Velvet' clone of degronianum ssp. yakushimanum var. yakushimanum
'White's Cunningham's Sulphur' clone of caucasicum
'Whitebait' A.M. 1966 clone of sargentianum
wightii sp. in subsection TALIENSIA
wilhelminae sp. in subgenus RHODODENDRON section VIREYA subsection MALAYOVIREYA
WILLIAMSIANA (subsection) subsection in subgenus HYMENANTHES
WILLIAMSIANUM subseries of THOMSONII series syn. subsection WILLIAMSIANA
williamsianum sp. in subsection WILLIAMSIANA
williamsii sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
willmotiae syn. R. hanceanum
'Wilson's Augustinii' clone of augustinii ssp. augustinii
wilsoniae syn. R. latoucheae var. ionanthum
wilsoniae var. ionanthum syn. R. lotoucheae var. ionanthum
wilsoniae var. wilsonae syn. R. latoucheae var. latoucheae
x wilsoni syn. R. Wilsoni grex
wilsonianum unplaced
wiltonii sp. in subsection TALIENSIA
'Windsor Park' clone of souliei
windsorii syn. R. arboreum ssp. arboreum
'Winifred Murray' clone of cephalanthum ssp. cephalanthum
'Winter Brightness' F.C.C. 1957 clone of mucronulatum
'Winter Sunset' clone of mucronulatum
wollastonii syn. R. wentianum
wologense sp. in subsection FORTUNEA
womersleyi sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
wongii sp. in subsection TRIFLORA
wrayi sp. in subsection IRRORATA
wrayi var. ellipticum syn. R. waryi
wrayi var. minor syn. R. wrayi
wrightianum var. cyclopense var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection VIREYA
wrightianum var. insulare var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection VIREYA
wrightianum var. ovalifolium syn. R. simulans
wrightianum var. piliferum syn. R. papuanum
wrightianum var. wrightianum var. of sp. in subgenus RHODODENDRON section VIREYA
   subsection VIREYA
wuense syn. R. faberi
wumingense sp. in subsection MADDENIA
wumengense var. of R. sphaeroblastum var. of sp. in subsection TALIENSIA
wuyishanicum unplaced

x xanthanthum R. citriniflorum x temenium
xanthanthum syn. R. x citriniflorum
xanthanthum var. of chaetomallum syn. R. x xanthanthum
xanthinum syn. R. trichocladum
xanthocodon syn. R. cinnabarinum ssp. xanthocodon
xanthocodon ssp. of R. cinnabarinum ssp. of sp. in subsection CINNABARINA
xanthoneuron syn. R. denudatum
xanthopetalum sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
xanthosporum syn. R. detonsum
xanthostephanum clones
     'Yellow Garland'
xanthostephanum sp. in subsection TEPHROPEPLA
xichangense sp. in subsection TRIFLORA
xiguense sp. in subsection LAPPONICA
xinganense sp. in section AZALEASTRUM
xiushanense syn. R. chrysocalyx
xizangense sp. in subsection SELENSIA

'Yabae' clone of R. kiusianum
'Yak-ity-yak' clone of R. degronianum ssp. yakushimanum var. yakushimanum
'Yaku Angel' clone of R. degronianum ssp. yakushimanum var. yakushimanum
yakuinsulare syn. R. scabrum ssp. scabrum
yakuinsulare var. of R. simsii syn. R. scabrum ssp. scabrum
yakumontanum sp. in subsection TSUTSUSI section BRACHYCALYX
yakumontanum ssp. of R. nudipes syn. R. yakumontanum
yakumontanum syn. R. nudipes var. nudipes
'Yaku Fairy' A.M. 1970 clone of R. keiskei
'Yakushimanum Exbury' clone of R. degronianum ssp. yakushimanum var. yakushimanum
yakushimanum syn. R. degronianum ssp. yakushimanum var. yakushimanum
yakushimanum ssp. of metternichii syn. R. degronianum ssp. yakushimanum var. yakushimanum
yakushimanum ssp. of degronianum syn. R. degronianum ssp. yakushimanum var. yakushimanum
yakushimanum syn. R. degronianum ssp. yakushimanum var. yakushimanum
yakushimanum ssp. makinoi syn. R. makinoi
yakushimanum var. of R. degronianum syn. R. degronianum ssp. yakushimanum var. yakushimanum
yakushimanum var. of ssp. yakushimanum of sp. degronianum in subsection PONTICA
yakushimanum var. of R. metternichii syn. R. degronianum ssp. yakushimanun var. yakushimanum
yakushimanum var. of R. degronianum syn. R. degronianum ssp. yakushimanum var. yakushimanum
'Yangtze Bend' A.M. 1965 clone of R. uvarifolium
yangmingshanense sp. in subgenus TSUTSUSI subsection TSUTSUSI
yanthinum syn. R. concinnum
yanthinum syn. R. trichocladum
yanthinum var. lepidanthum syn. R. concinnum
yaogangxianense sp. in subsection MADDENIA
yaoshanicum sp. in subenus TSUTSUSI section TSUTSUSI
yaragongense syn. R. nivale ssp. boreale
yedoense syn. R. yedoense var. yedoense
yedoense var. hallaisanense syn. R. yedoense var. poukanense
yedoense var. yedoense var. of sp. subgenus TSUTSUSI in section TSUTSUSI
yedoense var. poukhanense var. of sp. subgenus TSUTSUSI in subsection TSUTSUSI
yelliotii sp. in subgenus RHODODENDRON section VIREYA subsection ALBOVIREYA
'Yellow Bunting' A.M. 1964 clone of R. fletcheranum
'Yellow Fellow' A.M. 1979 clone of mekongense var. mekongense
'Yellow Garland' A.M. 1961 clone of R. xanthostephanum
yizangense sp. in subsection MADDENIA
yodogawa syn. R. yedoense var. yedoense
yongii sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
youngae ssp. of R. simiarum syn. R. adenopodum
youngae syn. R. adenopodum
'Yucondus' syn. R. x erythrocalyx
'Yufuzakura' clone of R. kiusianum
yui var. of R. augustinii syn. R. augustinii ssp. augustinii
yulongense var. of R. websteranum var. of sp. in subsection LAPPONICA
'Yum-Yum' A.M. 1964 clone of R. tsariense
yungchangense sp. in subsection MADDENIA
yungningense sp. in subsection LAPPONICA
yunnanense clones
     'Openwood'
yunnanense sp. in subsection TRIFLORA
'Yuugiri' clone of kiusianum
'Yuzuki' clone of R. kiusianum

zaleucum var. flaviflorum var. of sp. in subsection TRIFLORA
zaleucum var. pubifolium var. of sp. in subsection TRIFLORA
zaleucum var. zaleucum var. of sp. in subsection TRIFLORA
zeylanicum syn. R. arboreum ssp. zeylanicum
zeylanicum ssp. of R. arboreum ssp. of sp. in subsection ARBOREA
zheguense sp. in subsection LAPPONICA
zhongdianense sp. in subsection TALIENSIA
zippelii syn. R. citrinum var. citrinum
ziyuanense var. pachyphyllum var of sp. in subsection MACULIFERA
ziyuanense var. ziyuanense var. of sp. in subsection MACULIFERA
zoelleri sp. in subgenus RHODODENDRON section VIREYA subsection VIREYA
zollingeri sp. in subgenus RHODODENDRON section VIREYA subsection ALBOVIREYA
zollingeri var. latifolium syn. R. zollingeri
'Zuiko' clone of R. kiusianum