(H. Lév.) Fu
Description
Rhodiola chrysanthemifolia is a high-altitude succulent of the Himalaya and adjacent China, recorded from China, Nepal, India and Bhutan with more than 630 georeferenced occurrences. It is a plant of alpine meadows, rocky slopes, cliff crevices and stabilised screes, typically growing well above the treeline. The population photographed in the Zemu Valley of northern Sikkim at about 3450 m in August represents its characteristic alpine habitat, flowering and fruiting in late summer on cool, well-drained, often rocky substrates exposed to intense montane conditions.
The species is a glabrous perennial arising from a stout, woody, often branched caudex topped by a persistent rootstock. The annual flowering stems bear numerous alternate, fleshy leaves that are toothed to pinnately incised, the dissection recalling the foliage of Chrysanthemum and reflected in the epithet chrysanthemifolia. The flowers are grouped in dense terminal cymes; as in Rhodiola the plant is typically dioecious, with the small four- to five-merous flowers bearing distinct sepals and yellow to greenish-yellow or reddish-tinged petals. The fruit comprises erect, beaked follicles that split along the inner suture to release the small seeds.
Rhodiola, segregated from Sedum on the basis of its perennial caudex, dioecy and basally connate carpels, is a circumboreal and alpine Asian genus of considerable interest for its adaptogenic secondary chemistry. Several Himalayan congeners are intensively harvested for medicinal roots, placing wild populations under pressure, although R. chrysanthemifolia itself remains widespread and locally common across the high Himalaya and is not presently regarded as threatened.
Author: (H. Lév.) Fu · Sources: POWO (Kew), GBIF, Flora of Nepal, Flora of China, Flora of Bhutan, Ohba's studies of Himalayan Crassulaceae