This section is from the book "An Illustrated Flora Of The Northern United States, Canada And The British Possessions Vol1", by Nathaniel Lord Britton, Addison Brown. Also available from Amazon: An Illustrated Flora of the Northern United States, Canada and the British Possessions. 3 Volume Set..
A stout erect rough and puberulent herb, with alternate and opposite petioled digitately 5-11-divided thin leaves, persistent subulate stipules, and greenish dioecious axillary flowers, the staminate panicled, the pistillate spicate. Staminate flowers with a 5-parted calyx, the sepals distinct and imbricated, and 5 short stamens. Pistillate flowers solitary in the axils of foliaceous bracts, consisting of a thin entire calyx clasping the sessile ovary, and 2 filiform caducous stigmas. Fruit a compressed achene. Embryo curved. [The classic name of hemp.]
A monotypic genus of central Asia.
Cannabis sativa L. Sp. PI. 1027. 1753.
An annual branching herb, 3°-10° tall, the inner fibrous bark very tough, the branches nearly erect. Leaves divided to the base, the segments lanceolate or linear-lanceolate, acuminate at both ends, sharply and coarsely serrate, 3'-6' long, 1/4'-l' wide; staminate panicles narrow, loose, peduncled, 3-5' long; pedicels filiform, bracteolate, 1"-3" long; pistillate spikes erect, leafy-bracted, 1' long or less in fruit; achene crusta-ceous, ovoid-oblong, about 2" high.
In waste places, New Brunswick to Ontario and Minnesota, south to North Carolina, Tennessee and Kansas. Widely distributed in all temperate regions through cultivation, and occasionally a troublesome weed. Native of Europe and Asia. July-Sept. Gallow-grass. Neckweed.