Shi Nan Ye

Shi Nan Ye (石楠叶) is the dried leaf of Photinia serratifolia (Desf.) Kalkman (synonym Photinia serrulata Lindl.), an evergreen shrub or small tree in the Rosaceae reaching 4–12 m, widely distributed across central and southern China and cultivated as an ornamental for its brilliant red young growth. The leathery, oblong-elliptic to oblanceolate leaves measure 9–22 cm long with finely sharp-serrate margins and a prominent midrib; mature leaves are glossy dark green above and paler beneath. Flat-topped corymbs of small white five-petaled flowers in spring give rise to small globose red pomes. The dried leaves contain cyanogenic glycosides (notably prunasin) and are historically regarded as mildly toxic in excess; medicinal use is principally for wind-damp painful obstruction, lumbar weakness, and headache, with careful dosing.