7. Rhododendron subg. Pentanthera (G. Don) Pojarkova in Schischkin & Bobrov, Fl. URSS. 18: 57. 1952.
羊踯躅亚属 yang zhi zhu ya shu
He Mingyou (何明友); David F. Chamberlain
Rhododendron sect. Pentanthera G. Don, Gen. Hist. 3: 846. 1834.
Shrubs, erect, rarely treelike, deciduous; new leafy shoots from axils of leaves of past season; young shoots sometimes verticillate, not scaly, setose, pubescent or glabrous. Winter buds with many imbricate scales; branches and leaves arising from lower part of buds. Leaves scattered or verticillate. Leaf blade not scaly. Inflorescence terminal, arising from an apical bud on the previous year’s shoots, shortly racemose-umbellate, several- to many-flowered. Calyx usually small, rarely up to 6 mm; corolla funnel-campanulate, or rotate- to tubular-campanulate, tube ca. as long as, or markedly shorter than the lobes, sparsely pubescent on outer surface, often with glands, or glabrous, with or without flecks; stamens 5(–10), included or exserted; filaments puberulent below; ovary 5-locular, pubescent setose or glandular; style glabrous. Capsule with woody carpopodium.
About 24 species: mostly in North America, also in E and SW Asia and E and EC Europe; two species in China.