HODODENDRON SPECIES DICTIONARY Listing clones, valid and invalid synonyms, subspecies, varietys and forms By Herbert A. Spady Spadherb@AOL.com Copyright 1998 by Herbert A. Spady Published on the Internet 1998 by Herbert A. Spady COPYRIGHT NOTICE: This publication is copyrighted by the author. It may be reproduced in any form for personal use. It may not be reproduced in any form and sold by an individual (not even for cost of reproduction and distribution). However, it may be reproduced in any form by an individual and given away. It may be reproduced for sale by the American Rhododendron Society, any of its chapters, the Rhododendron Species Foundation or the Rhododendron Research Foundation without restrictions. INTRODUCTION: This publication represents a massive revision of the Rhododendron 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 section Vireya. Since that time extensive revision has taken place in the genus. This publication attempts to encompass those revisions and now includes section Vireya. The revision of the Genus Rhododendron 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 1025 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 For these reasons this effort is obsolete at the time that you read it, but it is hoped that it will be useful for some years to come.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 Tsutsusi Edinburgh 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. The goals have not changed. In 1984 time I indicated that I had felt a need for a dictionary of this type so I attempted to create it. There are ‘official’ publications that are similar, but do not encompass all the cross-referencing that I have attempted. The species, subspecies, varieties and forms are herein listed italicized in standard form. (This formatting is available only in the Microsoft Word download.) However, I have listed each under a secondary listing by subspecies, variety or form. I have made these entries because it has been my experience that species may at times be mentioned in the literature by what is now a subspecies, variety or form name. Under those circumstances the only way one can identify the presently accepted name is to have such a cross-reference. 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 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 VIREY 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 chanaecystys 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. decroum 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 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. intrmedium 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' '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 BRACHYCALY 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 toschonoskii 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 sectionBRACHYCALYX 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