Rou Dou Kou

Myristica fragrans Houtt. (Myristicaceae) is a dioecious, evergreen tropical tree native to the Banda Islands of Indonesia and now cultivated throughout the moist tropics. It reaches 5 to 20 meters in height with a spreading, conical crown and dark, smooth bark exuding a watery red sap when cut. The leaves are alternate, elliptic to oblong-lanceolate, 5 to 15 cm long, dark green and glossy above and paler below, with entire margins and a leathery texture. The small, pale yellow, fleshy, bell-shaped flowers are borne in axillary umbel-like cymes, the staminate and pistillate flowers usually on separate trees. The fruit is a fleshy, yellow, pear-shaped to globose drupe-like capsule 5 to 8 cm long that splits open at maturity into two valves, revealing a single ovoid seed covered by a brilliant red, lacy aril. The hard, brown, oval seed kernel constitutes nutmeg, used as Rou Dou Kou in Chinese medicine, while the dried aril is the spice mace.