Eucommia (Eucommia ulmoides) is a small tree native to China. It is near threatened in the wild, but is widely cultivated in China for its bark, and is highly valued in herbology such as Traditional Chinese medicine. Eucommia grows to about 15 m tall. The leaves are deciduous, arranged alternately, simple ovate with an acuminate tip, 8–16 cm long, and with a serrated margin. Eucommia is also occasionally planted in botanical gardens and other gardens in Europe, North America and elsewhere, being of interest as the only cold-tolerant (to at least -30°C) rubber-producing tree. Eucommia ulmoides Oliv. (Du-zhong), a well known Chinese herbal medicine, has been increasingly used as a nutraceutical supplement. Six compounds, namely pinoresinol 4′-O-β-d-glucopyranoside, pinoresinol di-O-β-d-glucopyranoside, aucubin, wogonin, baicalein, and α-O-β-d-glucopyranosyl-4,2′,4′-trihydroxydihydrochalcone.