Yuan Zhi

Polygala tenuifolia, the thinleaf milkwort, is a slender perennial herbaceous plant in the family Polygalaceae, native to dry, sunny grassland slopes, gravelly hillsides, and pine forests across northern China, Mongolia, Korea, and the Russian Far East. It grows from a long, cylindrical, slightly twisted, pale-yellow taproot with a wrinkled, somewhat spongy cortex that is easily separated from the woody central core. Multiple erect or ascending stems 15-40 cm tall rise from the crown, bearing numerous alternate, linear to narrowly oblanceolate leaves 1-3 cm long with entire margins. Small purple to bluish-violet papilionaceous flowers, each with three petals and two petaloid sepals (wings), are borne in slender terminal racemes. The fruit is a small, flattened, oblong capsule containing two seeds with white arils.