The rhizome and roots of hydrastis canadensis Linne, yielding not less
than 2.5 per cent of hydrastine.
HABITAT.--North America in woods west to Missouri and Arkansas.
PROPERTIES.--Externally brownish-gray to yellow-brown; fracture short,
wood wedges bright yellow, pith large, light yellow, the roots thin,
brittle, with a thick yellow bark and a somewhat quadrangular wood; odor
distinct; taste bitter.
CONSTITUENTS.--Berberine, an alkaloid occurring in yellow crystals;
hydrastine, a colorless crystalline alkaloid, soluble in alcohol and
ether; canadine occurring in white, acicular crystals.
DOSE.--Horses and cattle, 2 dr. to 1 oz.; sheep and pigs, 1 to 2 dr.;
dogs, 5 gr. to 1 dr.