135. Rhododendron micranthum Turczaninow, Bull. Soc. Imp. Naturalistes Moscou. 10(7): 155. 1837.
照山白 zhao shan bai
Rhododendron pritzelianum Diels; R. rosthornii Diels.
Shrubs, evergreen, up to 2.5 m tall; branchlets slender, scaly, puberulous. Petiole 3–8 mm, scaly; leaf blade almost leathery, oblanceolate, oblong-elliptic, to lanceolate, (1.5–)3–4(–6) × (0.4–)9–12(–2.5) cm; base narrowly cuneate; apex obtuse or acute, mucronate; abaxial surface scales contiguous or ca. 0.5 × their own diameter apart, brownish, broadly rimmed; adaxial surface dark green, shiny, usually sparsely scaly. Inflorescence racemose, 10–28-flowered; rachis 10–26 mm. Pedicel 0.8–2 cm, densely scaly; calyx lobes 1–3 mm, linear or triangular-lanceolate, scaly, margin ciliate; corolla campanulate, white, (0.4–) 0.5–0.8(–1) cm, tube slightly shorter than lobes; outer surface scaly; inner surface glabrous; stamens 10, nearly as long as corolla; filaments glabrous; ovary densely scaly; style nearly as long as stamens, glabrous. Capsule cylindric, (4–)5–6(–8) mm, scaly. Fl. May–Jun, fr. Aug–Nov.
Thickets, scrub, slopes, dry gorges, cliffs, rocks; 1000–3000 m. N China, also Henan, Hubei, Hunan, Sichuan [Korea].