Spirae'a tomento'sa, Hardhack. -- The root, U.S.P. 1820-1870; N. America; shrub, .6-1 M. (2-3 degrees) high, stem ferruginous, tomentous, leaves dark green, but rusty-white beneath; flowers purple; fruit 1-seeded pod; root consists of brown, bitter, astringent bark, and hard, white, tasteless wood; contains tannin, bitter principle, volatile oil. Astringent, tonic; diarrhea, cholera infantum, hemorrhages, gonorrhea, ulcers, etc.; infusion, decoction, extract. Dose 3ss-1 (2-4 Gm.).