Rhododendrons belong to the Ericaceae or heath family. Other members of the Ericaceae include the heaths (Erica), and heathers (Calluna), mountain laurel (Kalmia), lily-of-the-valley shrub (Pieris), cranberry (Vaccinium), Leucothe and Andromeda. Almost all of the heath family make good garden plants.
When Linnaeus created the botanical grouping called genus Rhododendron in 1753, he created a separate genus for Azaleas containing 6 species. In 1796 Salisbury pointed out that Azaleas and Rhododendrons could not be maintained as distinct genera. In 1834, George Don subdivided the genus Rhododendron into 8 sections which were recognized until 2004. Azaleas comprised two of these sections, Subgenus Pentanthera typified by Rhododendron nudiflorum and Subgenus Tsutsusi typified by Rhododendron Tsutsusi.
The extensive collections of Rhododendron in the early 1900's from southern Asia made by Forrest, Rock, Kingdom-Ward, and others stimulated taxonomic work at Edinburgh Botanic Garden and Herbarium under the direction of Bayley Balfour. The horticulturally based classification consists of about 45 series. The artificial classification was intended as a temporary measure, but it became firmly entrenched following the publication of The Species of Rhododendron in 1930 by the Royal Horticultural Society. This system was designed to cope with the vast quantities of new plant material received from the Orient, North America, etc. Balfour intended to revise the temporary system but died before it could be accomplished.
The Series system does not attempt to classify species under their subgenera and section as proposed in the International Rules of Botanical Nomenclature. Further, it is based largely on cultivated plants rather than Rhododendron found in the wild.
The Eight Subgenera prior to 2004
With many species discovered over several centuries the genus Rhododendron has been subdivided into groups and revised several times. . Up until 2004 the genus was divided into eight subgenera under the taxonomic system of Chamberlain et al. (1996):
The first four of these subgenera contain all species the entire genus except for five. Of the last four Candidastrum, Mumeazalea and Therorhodion each include only one species (R. albiflorum, R. semibarbatum and R. camtshaticum respectively) while Azaleastrum includes two species (R. ovatum and R. stamineum).
Subgenera Rhododendron and Hymenanthes include the plants that gardeners recognize as the "true" rhododendrons. Some of these, the lepidote rhododendrons, have small scales on their leaves and make up the subgenus Rhododendron. Elepidote rhododendrons, those without leaf scales, form the subgenus Hymenanthes.
Subgenus Pentanthera covered the deciduous azaleas and Tsutsutsi covered the evergreen azaleas. Neither of these Subgenus has scales.
A list of all species and their classification is provided in the Genus Rhododendron Taxonomic Tree
The Five Subgenera proposed in 2004
Based upon genetic and chemical data, in 2004, Loretta Goetsch, Andrew Eckert and Benjamin Hall of the University of Washington proposed and in 2005 published a recomendation that the Genus Rhododendron be revised and subdivided into five subgenera:
Some of the subgenera are divided into sections, which are further divided into subsections.
For taxa outside of subgenus Rhododendron, this system eliminates three subgenera and two sections that are present in the 1996 taxonomic system of Chamberlain et al.
Section Pentanthera is included within subgenus Hymenanthes.
Sections Sciadorhodion and Viscidula and R. vaseyi (section Rhodora) from the discontinued subgenus Pentanthera are combined with sections Azaleastrum, Tsutsusi and Brachycalyx to form an expanded and revised subgenus Azaleastrum. Sister groups in this subgenus are the sections Tsutsusi (largely evergreen) and Sciadorhodion (entirely deciduous)
Since Choniastrum lacks lepidote scales on the leaves, Goetsch et al. propose that Choniastrum be considered a separate subgenus.
After Dr. Hall presented this work at the ARS National Meeting in 2005, Norman Todd published a paper called "Hall's DNA". In this paper Todd states: "the DNA results obtained by Ben Hall do not support Pentanthera being a subgenus. He proposes that it now become part of Hymenanthes. The genetic differences are not significant enough to warrant sub generic rank. The ranking below Subgenus is Section. Hall proposes that Pentanthera be given a Section ranking. He proposes other changes in the other smaller subgenera ..."
If you understand the basic ideas of genus, subgenus, section and species you will have a better understanding of rhododendron naming conventions. A rhododendron species can be uniquely identified with the genus and species. Hence Rhododendron albiflorum defines a unique species. There may be another genus that uses the name albiflorum since it is Latin for "white flowering". Return to Top
This version of a proposed Taxonomic Tree of 774 species is based upon the similar tree published at:
http://www.flounder.ca/FraserSouth/tree.asp
SUBGENUS | SECTION | SUBSECTION | SPECIES | SUBSPECIES | VARIETY |
subgenus Azaleastrum | |||||
section Sciadorhodion | |||||
Rhododendron albiflorum | |||||
Rhododendron albrechtii | |||||
Rhododendron pentaphyllum | |||||
Rhododendron quinquefolium | |||||
Rhododendron schlippenbachii | |||||
Rhododendron vaseyi | |||||
section Tsutsusi | |||||
Rhododendron amagianum | |||||
Rhododendron atrovirens | |||||
Rhododendron breviperulatum | |||||
Rhododendron decandrum | |||||
Rhododendron dilatatum | |||||
Rhododendron eriocarpum | |||||
Rhododendron farrerae | |||||
Rhododendron hidakanum | |||||
Rhododendron hongkongense | |||||
Rhododendron indicum | |||||
Rhododendron kaempferi | |||||
Rhododendron kanehirai | |||||
Rhododendron kiusianum | |||||
var. kiusianum | |||||
var. sataense | |||||
Rhododendron kiyosumense | |||||
Rhododendron leptothrium | |||||
Rhododendron mariesii | |||||
Rhododendron mayebarae | |||||
Rhododendron microphyton | |||||
Rhododendron mucronatum | |||||
var. mucronatum | |||||
Rhododendron nakaharae | |||||
Rhododendron noriakianum | |||||
var. lagopus | |||||
ssp. niphophilum | |||||
ssp. nudipes | |||||
Rhododendron nudipes | |||||
ssp. nupides | |||||
ssp. niphophilum | |||||
Rhododendron oldhamii | |||||
Rhododendron ovatum | |||||
Rhododendron reticulatum | |||||
Rhododendron ripense | |||||
Rhododendron rubropilosum | |||||
Rhododendron sanctum | |||||
Rhododendron saxicolum | |||||
Rhododendron scabrum | |||||
Rhododendron semibarbatum | |||||
Rhododendron serpyllifolium | |||||
Rhododendron simsii | |||||
Rhododendron stenopetalum | |||||
Rhododendron subsessile | |||||
Rhododendron tashiroi | |||||
Rhododendron tosaense | |||||
Rhododendron tschonskii | |||||
Rhododendron tsuiophyllum | |||||
Rhododendron vialii | |||||
Rhododendron viscistylum | |||||
Rhododendron wadanum | |||||
Rhododendron weyrichii | |||||
Rhododendron yedoense | |||||
var. poukhanense | |||||
Rhododendron nipponicum | |||||
subgenus Choniastrum | |||||
Rhododendron championae | |||||
Rhododendron hancockii | |||||
Rhododendron latoucheae | |||||
Rhododendron moulmainense | |||||
Rhododendron stamineum | |||||
subgenus Hymenanthes | |||||
section Pentanthera | |||||
Rhododendron alabamense | |||||
Rhododendron arborescens | |||||
Rhododendron atlanticum | |||||
Rhododendron austrinum | |||||
Rhododendron calendulaceum | |||||
Rhododendron canadense | |||||
Rhododendron canescens | |||||
Rhododendron colemanii | |||||
Rhododendron cumberlandense | |||||
Rhododendron eastmanii | |||||
Rhododendron flammeum | |||||
Rhododendron luteum | |||||
Rhododendron molle | |||||
ssp. molle | |||||
ssp. japonicum | |||||
Rhododendron occidentale | |||||
Rhododendron periclymenoides | |||||
Rhododendron prinophyllum | |||||
Rhododendron prunifolium | |||||
Rhododendron viscosum | |||||
section Ponticum | |||||
subsection Arborea | |||||
Rhododendron arboreum | |||||
ssp. albotomentosum | |||||
ssp. arboreum | |||||
ssp. cinnamomeum | |||||
var. cinnamomeum | |||||
var. roseum | |||||
ssp. delavayi | |||||
var. delavayi | |||||
var. peramoenum | |||||
ssp. nilagiricum | |||||
ssp. zeylanicum | |||||
Rhododendron lanigerum | |||||
Rhododendron niveum | |||||
subsection Argyrophylla | |||||
Rhododendron adenopodum | |||||
Rhododendron argyrophyllum | |||||
ssp. argyrophyllum | |||||
ssp. hypoglaucum | |||||
ssp. omeinse | |||||
ssp. nankingense | |||||
Rhododendron coryanum | |||||
Rhododendron denudatum | |||||
Rhododendron floribundum | |||||
Rhododendron formosanum | |||||
Rhododendron haofui | |||||
Rhododendron hunnewellianum | |||||
Rhododendron insigne | |||||
Rhododendron longipes | |||||
var. chienianum | |||||
var. longipes | |||||
Rhododendron pingianum | |||||
Rhododendron ririei | |||||
Rhododendron simiarum | |||||
Rhododendron thayerianum | |||||
subsection Auriculata | |||||
Rhododendron auriculatum | |||||
subsection Barbata | |||||
Rhododendron argipeplum | |||||
Rhododendron barbatum | |||||
Rhododendron erosum | |||||
Rhododendron exasperatum | |||||
Rhododendron succothii | |||||
subsection Campanulata | |||||
Rhododendron campanulatum | |||||
ssp. campanulatum | |||||
ssp. aeruginosum | |||||
Rhododendron wallichii | |||||
subsection Campylocarpa | |||||
Rhododendron callimorphum | |||||
var. callimorphum | |||||
var. myiagrum | |||||
Rhododendron campylocarpum | |||||
ssp. campylocarpum | |||||
ssp. caloxanthum | |||||
Rhododendron souliei | |||||
Rhododendron wardii | |||||
var. puralbum | |||||
var. wardii | |||||
subsection Falconera | |||||
Rhododendron arizelum | |||||
Rhododendron basilicum | |||||
Rhododendron coriaceum | |||||
Rhododendron falconeri | |||||
ssp. eximium | |||||
ssp. falconeri | |||||
Rhododendron galactinum | |||||
Rhododendron hodgsonii | |||||
Rhododendron preptum | |||||
Rhododendron rex | |||||
ssp. fictolacteum | |||||
var miniforme | |||||
ssp. gratum | |||||
ssp. rex | |||||
Rhododendron rothschildii | |||||
Rhododendron semnoides | |||||
Rhododendron sinofalconeri | |||||
subsection Fortunea | |||||
Rhododendron asterochnoum | |||||
Rhododendron calophytum | |||||
var. calophytum | |||||
var. openshawianum | |||||
Rhododendron davidii | |||||
Rhododendron decorum | |||||
ssp. decorum | |||||
ssp. diaprepes | |||||
Rhododendron fortunei | |||||
ssp. discolor | |||||
ssp. fortunei | |||||
Rhododendron glanduliferum | |||||
Rhododendron griffithianum | |||||
Rhododendron hemsleyanum | |||||
Rhododendron huianum | |||||
Rhododendron orbiculare | |||||
ssp. cardiobasis | |||||
ssp. orbiculare | |||||
Rhododendron oreodoxa | |||||
var. fargesii | |||||
var. oreodoxa | |||||
var. shensiense | |||||
Rhododendron platypodum | |||||
Rhododendron praeteritum | |||||
Rhododendron praevernum | |||||
Rhododendron serotinum | |||||
Rhododendron sutchuenense | |||||
Rhododendron vernicosum | |||||
subsection Fulgensia | |||||
Rhododendron fulgens | |||||
subsection Fulva | |||||
Rhododendron fulvum | |||||
ssp. fulvum | |||||
ssp. fulvoides | |||||
Rhododendron uvariifolium | |||||
var. uvariifolium | |||||
var. griseum | |||||
subsection Glischra | |||||
Rhododendron adenosum | |||||
Rhododendron crinigerum | |||||
var. cringerum | |||||
var. euadenium | |||||
Rhododendron glischroides | |||||
Rhododendron glischrum | |||||
ssp. glischrum | |||||
ssp. rude | |||||
Rhododendron habrotrichum | |||||
Rhododendron recurvoides | |||||
Rhododendron spilotum | |||||
Rhododendron vesiculiferum | |||||
subsection Grandia | |||||
Rhododendron balangense | |||||
Rhododendron gongshanense | |||||
Rhododendron grande | |||||
Rhododendron kesangiae | |||||
var. kesangiae | |||||
var. album | |||||
Rhododendron macabeanum | |||||
Rhododendron magnificum | |||||
Rhododendron montroseanum | |||||
Rhododendron praestans | |||||
Rhododendron protistum | |||||
Rhododendron pudorosum | |||||
Rhododendron sidereum | |||||
Rhododendron sinogrande | |||||
Rhododendron watsonii | |||||
subsection Griersoniana | |||||
Rhododendron griersonianum | |||||
subsection Irrorata | |||||
Rhododendron aberconwayi | |||||
Rhododendron annae | |||||
ssp. annae | |||||
ssp. laxiflorum | |||||
Rhododendron anthosphaerum | |||||
Rhododendron araiophyllum | |||||
Rhododendron irroratum | |||||
ssp. irroratum | |||||
ssp. pogonostylum | |||||
Rhododendron kendrickii | |||||
Rhododendron ramsdenianum | |||||
Rhododendron tanastylum | |||||
var. pennivenium | |||||
var. tanastylum | |||||
Rhododendron wrayi | |||||
subsection Lanata | |||||
Rhododendron flinckii | |||||
Rhododendron lanatoides | |||||
Rhododendron lanatum | |||||
Rhododendron luciferum | |||||
Rhododendron tsariense | |||||
subsection Maculifera | |||||
Rhododendron anwheiense | |||||
Rhododendron longesquamatum | |||||
Rhododendron maculiferum | |||||
Rhododendron morii | |||||
Rhododendron ochraceum | |||||
Rhododendron pachysanthum | |||||
Rhododendron pachytrichum | |||||
Rhododendron pseudochrysanthum | |||||
Rhododendron sikangense | |||||
var. exquisitum | |||||
var. sikangense | |||||
Rhododendron strigillosum | |||||
subsection Neriiflora | |||||
Rhododendron albertsenianum | |||||
Rhododendron aperantum | |||||
Rhododendron beanianum | |||||
Rhododendron catacosmum | |||||
Rhododendron chamaethomsonii | |||||
var. chamaedoron | |||||
var. chamaethauma | |||||
var. chamaethomsonii | |||||
Rhododendron citriniflorum | |||||
var. citriniflorum | |||||
var. horaeum | |||||
Rhododendron coelicum | |||||
Rhododendron dichroanthum | |||||
ssp. apodectum | |||||
ssp. dichroanthum | |||||
ssp. scyphocalyx | |||||
ssp. septentrionale | |||||
Rhododendron euchroum | |||||
Rhododendron eudoxum | |||||
var. brunneifolium | |||||
var. eudoxum | |||||
var. mesopolium | |||||
Rhododendron floccigerum | |||||
Rhododendron forrestii | |||||
ssp. forestii | |||||
ssp. papillatum | |||||
Rhododendron haematodes | |||||
ssp. chaetomallum | |||||
ssp. haematodes | |||||
Rhododendron mallotum | |||||
Rhododendron microgynum | |||||
Rhododendron miniatum | |||||
Rhododendron neriiflorum | |||||
ssp. agetum | |||||
ssp. neriiflorum | |||||
ssp. phaedropum | |||||
Rhododendron parmulatum | |||||
Rhododendron piercei | |||||
Rhododendron pocophorum | |||||
var. hemidartum | |||||
var. pocophorum | |||||
Rhododendron sanguineum | |||||
ssp. didymum | |||||
ssp. sanguineum | |||||
var. cloiophorum | |||||
var. didymoides | |||||
var. himertum | |||||
var. sanguineum | |||||
Rhododendron sperabile | |||||
var. sperabile | |||||
var. weihsiense | |||||
Rhododendron sperabiloides | |||||
Rhododendron temenium | |||||
var. dealbatum | |||||
var. gilvum | |||||
var. temenium | |||||
subsection Parishia | |||||
Rhododendron elliotti | |||||
Rhododendron facetum | |||||
Rhododendron kyawii | |||||
subsection Pontica | |||||
Rhododendron aureum | |||||
var. aureum | |||||
var. hypopytis | |||||
Rhododendron brachycarpum | |||||
ssp. brachycarpum | |||||
ssp. fauriei | |||||
Rhododendron catawbiense | |||||
Rhododendron caucasicum | |||||
Rhododendron degronianum | |||||
ssp. degronianum | |||||
ssp. heptamerum | |||||
var. heptamerum | |||||
var. hondoense | |||||
var. kyomaruense | |||||
ssp. yakushimanum | |||||
Rhododendron hyperythrum | |||||
Rhododendron macrophyllum | |||||
Rhododendron makinoi | |||||
Rhododendron maximum | |||||
Rhododendron ponticum | |||||
Rhododendron smirnowii | |||||
Rhododendron ungernii | |||||
subsection Selensia | |||||
Rhododendron bainbridgeanum | |||||
Rhododendron dasycladoides | |||||
ssp. jucundum | |||||
ssp. setiferum | |||||
Rhododendron esetulosum | |||||
Rhododendron hirtipes | |||||
Rhododendron martinanum | |||||
Rhododendron selense | |||||
ssp. dasycladum | |||||
ssp. selense | |||||
subsection Taliensia | |||||
Rhododendron adenogynum | |||||
Rhododendron aganniphum | |||||
var. aganniphum | |||||
var. flavorufum | |||||
Rhododendron alutaceum | |||||
var. alutaceum | |||||
var. iodes | |||||
var. russotinctum | |||||
Rhododendron balfourianum | |||||
Rhododendron bathyphyllum | |||||
Rhododendron beesianum | |||||
Rhododendron bhutanense | |||||
Rhododendron bureavii | |||||
Rhododendron bureaviodes | |||||
Rhododendron clementinae | |||||
Rhododendron coeloneuron | |||||
Rhododendron dignabile | |||||
Rhododendron elegantulum | |||||
Rhododendron faberi | |||||
Rhododendron inopinum | |||||
Rhododendron lacteum | |||||
Rhododendron mimetes | |||||
var. mimetes | |||||
var. simulans | |||||
Rhododendron nigroglandulsom | |||||
Rhododendron paradoxum | |||||
Rhododendron phaeochrysum | |||||
var. agglutinatum | |||||
var. levistratum | |||||
var. phaeochrysum | |||||
Rhododendron prattii | |||||
Rhododendron principis | |||||
Rhododendron pronum | |||||
Rhododendron proteoides | |||||
Rhododendron przewalskii | |||||
ssp. dabanshanense | |||||
ssp. przewalskii | |||||
Rhododendron purdomii | |||||
Rhododendron roxieanum | |||||
var. cucullatum | |||||
var. oreonastes | |||||
var. roxieanum | |||||
Rhododendron rufum | |||||
Rhododendron sphaeroblatum | |||||
var. wumengense | |||||
Rhododendron taliense | |||||
Rhododendron traillianum | |||||
var. dictyotum | |||||
var. traillianum | |||||
Rhododendron wasonii | |||||
var. wenchuanense | |||||
Rhododendron wightii | |||||
Rhododendron wiltonii | |||||
subsection Thomsonia | |||||
Rhododendron cerasinum | |||||
Rhododendron cyanocarpum | |||||
Rhododendron eclecteum | |||||
var. bellatulum | |||||
Rhododendron faucium | |||||
Rhododendron hylaeum | |||||
Rhododendron hookeri | |||||
Rhododendron meddianum | |||||
var. atrokermesinum | |||||
var. meddianum | |||||
Rhododendron sherriffii | |||||
Rhododendron stewartianum | |||||
Rhododendron subansiriense | |||||
Rhododendron thomsonii | |||||
ssp. lopsangianum | |||||
ssp. thomsonii | |||||
Rhododendron viscidifolium | |||||
subsection Venatora | |||||
Rhododendron venator | |||||
subsection Williamsiana | |||||
Rhododendron williamsianum | |||||
subgenus Rhododendron | |||||
section Pogonanthum | |||||
Rhododendron anthopogon | |||||
ssp. anthopogon | |||||
ssp. hypenanthum | |||||
Rhododendron anthopogonoides | |||||
Rhododendron cephalanthum | |||||
ssp. cephalanthum | |||||
ssp. platyphllum | |||||
Rhododendron collettianum | |||||
Rhododendron fragrans | |||||
Rhododendron kongboense | |||||
Rhododendron laudandum | |||||
var. laudandum | |||||
var. temoense | |||||
Rhododendron primuliflorum | |||||
Rhododendron sargentianum | |||||
Rhododendron trichostomum | |||||
section Rhododendron | |||||
subsection Afghanica | |||||
Rhododendron afghanicum | |||||
subsection Baileya | |||||
Rhododendron baileyi | |||||
subsection Boothia | |||||
Rhododendron boothii | |||||
Rhododendron chrysodoron | |||||
Rhododendron dekatanum | |||||
Rhododendron leptocarpum | |||||
Rhododendron leucaspis | |||||
Rhododendron megeratum | |||||
Rhododendron sulfureum | |||||
subsection Camelliiflora | |||||
Rhododendron camelliiflorum | |||||
subsection Campylogynum | |||||
Rhododendron campylogynum | |||||
subsection Caroliniana | |||||
Rhododendron minus | |||||
var. champmanii | |||||
var. minus | |||||
subsection Cinnabarinum | |||||
Rhododendron cinnabarinum | |||||
ssp. cinnabarinum | |||||
ssp. tamaense | |||||
ssp. xanthocodon | |||||
Rhododendron keysii | |||||
subsection Edgeworthia | |||||
Rhododendron edgeworthii | |||||
Rhododendron pendulum | |||||
Rhododendron seinghkuense | |||||
subsection Fragariflora | |||||
Rhododendron fragariiflorum | |||||
subsection Genestieriana | |||||
Rhododendron genestierianum | |||||
subsection Glauca | |||||
Rhododendron brachyanthum | |||||
ssp. brachyanthum | |||||
ssp. hypolepidotum | |||||
Rhododendron charitopes | |||||
ssp. charitopes | |||||
ssp. tsangpoense | |||||
Rhododendron glaucophyllum | |||||
var. album | |||||
var. glaucophyllum | |||||
var. tubiforme | |||||
Rhododendron luteiflorum | |||||
Rhododendron pruniflorum | |||||
Rhododendron shweliense | |||||
subsection Heliolepida | |||||
Rhododendron bracteatum | |||||
Rhododendron heliolepis | |||||
var. brevistylum | |||||
var. fumidum | |||||
var. heliolepis | |||||
Rhododendron rubiginosum | |||||
subsection Lapponica | |||||
Rhododendron bulu | |||||
Rhododendron capitatum | |||||
Rhododendron complexum | |||||
Rhododendron cuneatum | |||||
Rhododendron dasypetalum | |||||
Rhododendron fastigiatum | |||||
Rhododendron flavidum | |||||
Rhododendron hippophaeoides | |||||
var. hippophaeoides | |||||
var. occidentale | |||||
Rhododendron impeditum | |||||
Rhododendron intricatum | |||||
Rhododendron lapponicum | |||||
Rhododendron nitidulum | |||||
var. nitidulum | |||||
var. omeiense | |||||
Rhododendron nivale | |||||
ssp. australe | |||||
ssp. boreale | |||||
ssp. nivale | |||||
Rhododendron orthocladum | |||||
var. microleucum | |||||
var. orthocladum | |||||
Rhododendron polycladum | |||||
Rhododendron rupicola | |||||
var. chryseum | |||||
var. muliense | |||||
var. rupicola | |||||
Rhododendron russatum | |||||
Rhododendron setosum | |||||
Rhododendron tapetiforme | |||||
Rhododendron telmateium | |||||
Rhododendron thymiflolium | |||||
Rhododendron tsaii | |||||
Rhododendron websterianum | |||||
Rhododendron yungningense | |||||
subsection Ledum | |||||
Rhododendron groenlandicum | |||||
Rhododendron hypoleucum | |||||
Rhododendron neoglandulosum | |||||
Rhododendron subarcticum | |||||
Rhododendron subulatum | |||||
Rhododendron tolmachevii | |||||
Rhododendron tomentosum | |||||
subsection Lepidota | |||||
Rhododendron cowanianum | |||||
Rhododendron lepidotum | |||||
Rhododendron lowndesii | |||||
subsection Maddenia | |||||
Rhododendron burmanicum | |||||
Rhododendron carneum | |||||
Rhododendron ciliatum | |||||
Rhododendron coxianum | |||||
Rhododendron dalhousiae | |||||
var. dalhousiae | |||||
var. rhabdotum | |||||
Rhododendron dendricola | |||||
Rhododendron excellens | |||||
Rhododendron fletcherianum | |||||
Rhododendron formosum | |||||
var. formosum | |||||
var. inaequale | |||||
Rhododendron horlickianum | |||||
Rhododendron johnstoneanum | |||||
Rhododendron leptocladon | |||||
Rhododendron levinei | |||||
Rhododendron liliiflorum | |||||
Rhododendron lindleyi | |||||
Rhododendron ludwigianum | |||||
Rhododendron lyi | |||||
Rhododendron maddenii | |||||
ssp. crassum | |||||
ssp. maddenii | |||||
Rhododendron megacalyx | |||||
Rhododendron nuttallii | |||||
Rhododendron pachypodum | |||||
Rhododendron pseudociliipes | |||||
Rhododendron roseatum | |||||
Rhododendron scopulorum | |||||
Rhododendron taggianum | |||||
Rhododendron valentinianum | |||||
Rhododendron veitchianum | |||||
Rhododendron walongense | |||||
subsection Micrantha | |||||
Rhododendron micranthum | |||||
subsection Monantha | |||||
Rhododendron concinnoides | |||||
Rhododendron flavantherum | |||||
Rhododendron kasoense | |||||
Rhododendron monanthum | |||||
subsection Moupinensia | |||||
Rhododendron dendrocharis | |||||
Rhododendron moupinense | |||||
Rhododendron petrocharis | |||||
subsection Rhododendron | |||||
Rhododendron ferrugineum | |||||
Rhododendron hirsutum | |||||
Rhododendron myrtifolium | |||||
subsection Rhodorastra | |||||
Rhododendron dauricum | |||||
Rhododendron mucronulatum | |||||
var. mucronulatum | |||||
var. taquetii | |||||
Rhododendron sichotense | |||||
subsection Saluenensia | |||||
Rhododendron calostrotum | |||||
ssp. calostrotum | |||||
ssp. keleticum | |||||
ssp. riparioides | |||||
ssp. riparium | |||||
Rhododendron saluenense | |||||
ssp. chameunum | |||||
ssp. saluenense | |||||
subsection Scabrifolia | |||||
Rhododendron hemitrichotum | |||||
Rhododendron mollicomum | |||||
Rhododendron pubescens | |||||
Rhododendron racemosum | |||||
Rhododendron scabrifolium | |||||
var. pauciflorum | |||||
var. scabrifolium | |||||
var. spiciferum | |||||
Rhododendron spinuliferum | |||||
subsection Tephropepia | |||||
Rhododendron auritum | |||||
Rhododendron hanceanum | |||||
Rhododendron longistylum | |||||
Rhododendron tephropeplum | |||||
Rhododendron xanthostephanum | |||||
subsection Trichoclada | |||||
Rhododendron caesium | |||||
Rhododendron lepidostylum | |||||
Rhododendron mekongense | |||||
var. mekongense | |||||
var. rubrolineatum | |||||
Rhododendron trichocladum | |||||
Rhododendron viridescens | |||||
subsection Triflora | |||||
Rhododendron ambiguum | |||||
Rhododendron augustinii | |||||
ssp. augustinii | |||||
ssp. chasmanthum | |||||
ssp. hardyi | |||||
ssp. rubrum | |||||
Rhododendron concinnum | |||||
Rhododendron davidsonianum | |||||
Rhododendron keiskei | |||||
var. keiski | |||||
var. ozawae | |||||
Rhododendron lutescens | |||||
Rhododendron oreotrephes | |||||
Rhododendron polylepis | |||||
Rhododendron rigidum | |||||
Rhododendron seariane | |||||
Rhododendron siderophyllum | |||||
Rhododendron tatsienense | |||||
Rhododendron trichanthum | |||||
Rhododendron triflorum | |||||
var. bauhiniiflorum | |||||
var. triflorum | |||||
Rhododendron yunnanense | |||||
Rhododendron zaleucum | |||||
var. zaleucum | |||||
var. flaviflorum | |||||
subsection Uniflora | |||||
Rhododendron imperator | |||||
Rhododendron ludlowii | |||||
Rhododendron pemakoense | |||||
Rhododendron pumilum | |||||
Rhododendron uniflorum | |||||
subsection Virgata | |||||
Rhododendron virgatum | |||||
ssp. virgatum | |||||
ssp. oleifolium | |||||
section Vireya | |||||
subsection Albovireya | |||||
Rhododendron aequabile | |||||
Rhododendron album | |||||
Rhododendron arenicolum | |||||
Rhododendron cernuum | |||||
Rhododendron comptum | |||||
var. trichodes | |||||
Rhododendron correoides | |||||
Rhododendron giulianetti | |||||
Rhododendron lagunculicarpum | |||||
Rhododendron lampongum | |||||
Rhododendron proliferum | |||||
Rhododendron pudorinum | |||||
Rhododendron versteegii | |||||
Rhododendron yelliotii | |||||
Rhododendron zollingeri | |||||
subsection Malayovireya | |||||
Rhododendron acuminatum | |||||
Rhododendron apoanum | |||||
Rhododendron durionifolium | |||||
ssp. sabahense | |||||
Rhododendron fallacinum | |||||
Rhododendron fortunans | |||||
Rhododendron himantodes | |||||
var. lavandulifolium | |||||
Rhododendron lamrialianum | |||||
var. gunsalamianum | |||||
Rhododendron lineare | |||||
Rhododendron malayanum | |||||
var. axillare | |||||
var. axillare latifolium | |||||
var. axillare ovatum | |||||
var. infrapilosum | |||||
var. pilosifilum | |||||
var. pubens | |||||
Rhododendron micromalayanum | |||||
Rhododendron nortoniae | |||||
Rhododendron obscurum | |||||
Rhododendron variolosum | |||||
var. andersonii | |||||
Rhododendron vinicolor | |||||
subsection Phaeovireya | |||||
Rhododendron asperrimum | |||||
Rhododendron asperum | |||||
Rhododendron beyerinckianum | |||||
Rhododendron bryophilum | |||||
Rhododendron bullifolium | |||||
Rhododendron caliginis | |||||
Rhododendron cyatheicolum | |||||
Rhododendron delicatulum | |||||
var. lanceolatoides | |||||
Rhododendron dianthosmum | |||||
Rhododendron dielsianum | |||||
var. stylotrichum | |||||
Rhododendron extrorsum | |||||
Rhododendron eymae | |||||
Rhododendron gardenia | |||||
Rhododendron gilliardii | |||||
Rhododendron haematophthalmum | |||||
Rhododendron hellwigii | |||||
Rhododendron hooglandii | |||||
Rhododendron hyacinthosmum | |||||
Rhododendron kerowagiense | |||||
Rhododendron konori | |||||
var. phaeopeplum | |||||
Rhododendron leptanthum | |||||
var. warianum | |||||
Rhododendron melantherum | |||||
Rhododendron neriifolium | |||||
Rhododendron opulentum | |||||
Rhododendron phaeochitum | |||||
Rhododendron phaeochristum | |||||
Rhododendron phaeops | |||||
Rhododendron prainianum | |||||
Rhododendron psilanthum | |||||
Rhododendron rappardii | |||||
Rhododendron rarum | |||||
Rhododendron revolutum | |||||
Rhododendron rhodochroum | |||||
Rhododendron rubellum | |||||
Rhododendron schoddei | |||||
Rhododendron solitarium | |||||
Rhododendron spondylophyllum | |||||
Rhododendron stelligerum | |||||
Rhododendron stolleanum | |||||
Rhododendron superbum | |||||
Rhododendron thaumasianthum | |||||
Rhododendron truncicolum | |||||
Rhododendron tuberculiferum | |||||
subsection Pseudovireya | |||||
Rhododendron adinophyllum | |||||
Rhododendron asperulum | |||||
Rhododendron borneense | |||||
ssp. angustissimum | |||||
ssp. villosum | |||||
Rhododendron buxoides | |||||
Rhododendron capellae | |||||
Rhododendron ciliilobum | |||||
Rhododendron cuneifolium | |||||
var. microcarpum | |||||
Rhododendron cyrtophyllum | |||||
Rhododendron datiandingense | |||||
Rhododendron densifolium | |||||
Rhododendron emarginatum | |||||
var. eriocarpum | |||||
Rhododendron ericoides | |||||
Rhododendron erosipetalum | |||||
Rhododendron gaultheriifolium | |||||
var. expositum | |||||
Rhododendron hameliiflorum | |||||
Rhododendron insculptum | |||||
Rhododendron kawakamii | |||||
Rhododendron leiboense | |||||
Rhododendron lindaueanum | |||||
var. bantaengense | |||||
Rhododendron maguanense | |||||
Rhododendron meliphagidum | |||||
Rhododendron nanophyton | |||||
var. petrophilum | |||||
Rhododendron nummatum | |||||
Rhododendron oreites | |||||
var. chlorops | |||||
Rhododendron perakense | |||||
Rhododendron pulleanum | |||||
var. maiusculum | |||||
Rhododendron quadrasianum | |||||
var. davaoense | |||||
var. intermedium | |||||
var. malindangense | |||||
var. marivelesense | |||||
var. rosmarinifolium | |||||
var. selebicum | |||||
Rhododendron retusum | |||||
var. epilosum | |||||
var. trichostylum | |||||
Rhododendron rupivalleculatum | |||||
Rhododendron rushforthii | |||||
Rhododendron santapaui | |||||
Rhododendron saruwagedicum | |||||
Rhododendron schizostigma | |||||
Rhododendron scortechinii | |||||
Rhododendron seimundii | |||||
Rhododendron sororium | |||||
Rhododendron spathulatum | |||||
Rhododendron taxoides | |||||
Rhododendron vaccinioides | |||||
Rhododendron vanderbiltianum | |||||
Rhododendron vinkii | |||||
subsection Siphonovireya | |||||
Rhododendron agathodaemonis | |||||
Rhododendron cinchoniflorum | |||||
Rhododendron gideonii | |||||
Rhododendron habbemae | |||||
Rhododendron herzogii | |||||
Rhododendron incommodum | |||||
Rhododendron inundatum | |||||
Rhododendron protandrum | |||||
Rhododendron reevei | |||||
subsection Solenovireya | |||||
Rhododendron alborugosum | |||||
Rhododendron amabile | |||||
Rhododendron archboldianum | |||||
Rhododendron armitii | |||||
Rhododendron brachypodarium | |||||
Rhododendron carrii | |||||
Rhododendron carringtoniae | |||||
Rhododendron carstensense | |||||
Rhododendron chamaepitys | |||||
Rhododendron cinerascens | |||||
Rhododendron cruttwellii | |||||
Rhododendron edanoi | |||||
ssp. pneumonanthum | |||||
Rhododendron goodenoughii | |||||
Rhododendron hartleyi | |||||
Rhododendron jasminiflorum | |||||
var. copelandii | |||||
var. heusseri | |||||
var. oblongifolium | |||||
var. punctatum | |||||
Rhododendron lambianum | |||||
Rhododendron loranthiflorum | |||||
ssp. lakekamuensis | |||||
Rhododendron macrosiphon | |||||
Rhododendron maius | |||||
Rhododendron mendumiae | |||||
Rhododendron mogeanum | |||||
Rhododendron multinervium | |||||
Rhododendron natalicium | |||||
Rhododendron niveoflorum | |||||
Rhododendron oliganthum | |||||
Rhododendron orbiculatum | |||||
Rhododendron oreadum | |||||
Rhododendron pleianthum | |||||
Rhododendron pseudotricanthum | |||||
Rhododendron pubitubum | |||||
Rhododendron radians | |||||
var. minahasae | |||||
Rhododendron retrorsipilum | |||||
Rhododendron rhodoleucum | |||||
Rhododendron rhodosalpinx | |||||
Rhododendron roseiflorum | |||||
Rhododendron ruttenii | |||||
Rhododendron searleanum | |||||
Rhododendron stapfianum | |||||
Rhododendron suaveolens | |||||
var. roseum | |||||
Rhododendron subpacificum | |||||
Rhododendron syringoideum | |||||
Rhododendron tuba | |||||
Rhododendron | |||||
subsection Vireya | |||||
Rhododendron abietifolium | |||||
Rhododendron acrophilum | |||||
Rhododendron alternans | |||||
Rhododendron alticolum | |||||
Rhododendron anagalliflorum | |||||
Rhododendron angulatum | |||||
Rhododendron apiense | |||||
Rhododendron arfakianum | |||||
Rhododendron atropurpureum | |||||
Rhododendron aurigeranum | |||||
ssp. hirsutum | |||||
Rhododendron baconii | |||||
Rhododendron baenitzianum | |||||
Rhododendron bagobonum | |||||
Rhododendron banghamiorum | |||||
Rhododendron beccarii | |||||
Rhododendron blackii | |||||
Rhododendron bloembergenii | |||||
Rhododendron brachygynum | |||||
Rhododendron brassii | |||||
Rhododendron brevipes | |||||
Rhododendron burttii | |||||
Rhododendron buruense | |||||
Rhododendron buxifolium | |||||
Rhododendron caespitosum | |||||
Rhododendron calosanthes | |||||
Rhododendron celebicum | |||||
Rhododendron chevalieri | |||||
Rhododendron christi | |||||
Rhododendron christianae | |||||
Rhododendron citrinum | |||||
var. discoloratum | |||||
Rhododendron coelorum | |||||
Rhododendron commonae | |||||
Rhododendron commutatum | |||||
Rhododendron comparabile | |||||
Rhododendron cornu-bovis | |||||
Rhododendron crassifolium | |||||
Rhododendron culminicolum | |||||
var. angiense | |||||
var. nubicola | |||||
Rhododendron curviflorum | |||||
Rhododendron cuspidellum | |||||
Rhododendron detznerianum | |||||
Rhododendron disterigmoides | |||||
ssp. astromontium | |||||
Rhododendron englerianum | |||||
Rhododendron exuberans | |||||
Rhododendron flavoviride | |||||
Rhododendron frey-wysslingii | |||||
Rhododendron glabriflorum | |||||
Rhododendron gracilentum | |||||
Rhododendron hatamense | |||||
Rhododendron helodes | |||||
Rhododendron hirtolepidotum | |||||
Rhododendron impositum | |||||
Rhododendron impressopunctatum | |||||
Rhododendron inconspicuum | |||||
Rhododendron intranervatum | |||||
Rhododendron javanicum | |||||
ssp. brookeanum | |||||
ssp. cockburnii | |||||
ssp. palawanense | |||||
ssp. schadenbergii | |||||
var. teysmannii | |||||
Rhododendron kemulense | |||||
Rhododendron kochii | |||||
Rhododendron laetum | |||||
Rhododendron lamii | |||||
Rhododendron lanceolatum | |||||
Rhododendron leptobrachion | |||||
Rhododendron leptomorphum | |||||
Rhododendron leucogigas | |||||
Rhododendron leytense | |||||
var. loheri | |||||
Rhododendron loboense | |||||
Rhododendron lochiae | |||||
Rhododendron loerzingii | |||||
Rhododendron lompohense | |||||
Rhododendron longiflorum | |||||
var. bancanum | |||||
var. longipetalum | |||||
var. subcordatum | |||||
Rhododendron lowii | |||||
Rhododendron luraluense | |||||
Rhododendron luteosquamatum | |||||
Rhododendron macgregoriae | |||||
var. glabrifilum | |||||
var. mayrii | |||||
Rhododendron madulidii | |||||
Rhododendron maxwellii | |||||
Rhododendron meijeri | |||||
Rhododendron microphyllum | |||||
Rhododendron mindanaense | |||||
Rhododendron mollianum | |||||
Rhododendron monkoboense | |||||
Rhododendron multicolor | |||||
Rhododendron muscicola | |||||
Rhododendron myrsinites | |||||
Rhododendron neobritannicum | |||||
Rhododendron nervulosum | |||||
Rhododendron nieuwenhuisii | |||||
Rhododendron oxycoccoides | |||||
Rhododendron pachycarpon | |||||
Rhododendron pachystigma | |||||
Rhododendron papuanum | |||||
Rhododendron parvulum | |||||
Rhododendron pauciflorum | |||||
var. calocodon | |||||
Rhododendron perplexum | |||||
Rhododendron polyanthemum | |||||
Rhododendron poremense | |||||
Rhododendron porphyranthes | |||||
Rhododendron praetervisum | |||||
Rhododendron psammogenes | |||||
Rhododendron pseudobuxifolium | |||||
Rhododendron pseudomurudense | |||||
Rhododendron pubigermen | |||||
Rhododendron purpureiflorum | |||||
Rhododendron pusillum | |||||
Rhododendron pyrrhophorum | |||||
Rhododendron rarilepidotum | |||||
var. ootrichum | |||||
Rhododendron renschianum | |||||
Rhododendron retivenium | |||||
Rhododendron reynosoi | |||||
Rhododendron rhodopus | |||||
Rhododendron rhodostomum | |||||
Rhododendron ripleyi | |||||
var. basitrichum | |||||
var. cryptogonium | |||||
Rhododendron robinsonii | |||||
Rhododendron rosendahlii | |||||
Rhododendron rousei | |||||
Rhododendron rubineiflorum | |||||
Rhododendron rubrobracteatum | |||||
Rhododendron rugosum | |||||
var. kinabaluense | |||||
Rhododendron salicifolium | |||||
Rhododendron sarcodes | |||||
Rhododendron saxifragoides | |||||
Rhododendron sayeri | |||||
Rhododendron scabridibracteum | |||||
Rhododendron scarlatinum | |||||
Rhododendron schlechteri | |||||
Rhododendron seranicum | |||||
Rhododendron sessilifolium | |||||
Rhododendron simulans | |||||
Rhododendron stenophyllum | |||||
ssp. angustifolium | |||||
Rhododendron stevensianum | |||||
Rhododendron stresemanii | |||||
Rhododendron subcrenulatum | |||||
Rhododendron subuliferum | |||||
Rhododendron subulosum | |||||
Rhododendron sumatranum | |||||
Rhododendron takeuchii | |||||
Rhododendron taxifolium | |||||
Rhododendron toxopei | |||||
Rhododendron triumphans | |||||
Rhododendron tuhanensis | |||||
Rhododendron ultimum | |||||
Rhododendron vanvuurenii | |||||
Rhododendron verticillatum | |||||
var. velutinum | |||||
Rhododendron vidalii | |||||
ssp. brachystemon | |||||
Rhododendron villosulum | |||||
Rhododendron viriosum | |||||
Rhododendron vitis-idaea | |||||
Rhododendron wentianum | |||||
Rhododendron whiteheadii | |||||
Rhododendron wilkiei | |||||
Rhododendron williamsii | |||||
Rhododendron womersleyi | |||||
Rhododendron wrightianum | |||||
var. cyclopense | |||||
var. insulare | |||||
Rhododendron xanthopetalum | |||||
Rhododendron xenium | |||||
Rhododendron yongii | |||||
Rhododendron zoelleri | |||||
subgenus Therorhodion | |||||
Rhododendron camtschaticum | |||||
ssp. camtschaticum | |||||
ssp. glandulosum | |||||
Rhododendron redowskianun |