Huo Ma Ren

Cannabis sativa is a fast-growing annual herb in the Cannabaceae, probably native to central Asia and now cultivated worldwide for fibre, oilseed and medicinal preparations. The plant produces an erect, often single, ridged and hairy stem 1 to 4 meters tall, with palmately compound leaves arranged oppositely below and alternately above. Each leaf has 3 to 11 lanceolate, sharply serrate leaflets joined at a single point on a long petiole, with a deep green, slightly rough upper surface and a paler underside studded with resinous glandular trichomes, especially on female inflorescences. The species is typically dioecious. Male plants bear loose, branching panicles of small, five-parted, pendulous greenish-yellow flowers shedding wind-borne pollen; female plants produce dense leafy spikes of single-flowered axillary clusters with a tubular perianth enclosing the ovary. The fruit is a small, smooth, somewhat lens-shaped achene (the hemp seed) 3 to 5 mm long, greyish-brown and often mottled, containing a single oily seed. The dried ripe seed constitutes the Chinese drug Huo Ma Ren.