Zhu Ru

Phyllostachys nigra var. henonis is a large, fast-growing, running bamboo in the Poaceae family, native to China and widely cultivated for timber and medicinal use. It forms open groves of erect, woody culms reaching 7-18 meters in height and 5-10 cm in diameter at the base, with internodes 25-40 cm long. Unlike the type variety with black culms, this variety retains green to yellow-green stems throughout life, becoming slightly grooved above each branched node. The branches bear narrowly lanceolate leaves, 6-10 cm long and 1-1.5 cm wide, with finely serrate margins and tessellated venation. Flowering is rare and gregarious, occurring at long intervals. For TCM use, sections of fresh young culm are taken; the green outer epidermis is scraped away and the underlying pale-green inner stem is shaved into thin curling strips (Zhu Ru). Zhu Ru is classified as a sweet, slightly cold herb that clears heat and resolves phlegm.