Perennial herb to 2 m tall Stem: erect, unbranched or branched. Leaves: pinnately compound, stalked (with stipules), with well-developed lower leaves (to 50 cm long) and increasingly smaller upper leaves, bearing seven to seventeen leaflets. Flowers: borne on cylindrical spikes 3 - 20 cm long, white, lacking petals but having four petal-like sepals (2 - 3 mm long), four erect stamens, and one pistil. Fruit: a single achene enclosed in a four-angled calyx tube. Leafets: stalked, 2.5 - 10 cm long, egg-shaped to oblong or elliptic with a heart-shaped to rounded base and a blunt tip, toothed.
Similar species: Sanguisorba minor differs by having 2 cm or smaller main leaflets, two pistils, two achenes, and many drooping stamens.
Flowering: September
Habitat and ecology: Very rare in moist prairies.
Occurence in the Chicago region: native
Etymology: Sanguisorba comes from the Latin words sanguis, meaning blood, and sorbeo, meaning "to soak up," referring to the once-thought ability of the plant to stop bleeding by contracting the blood vessels. Canadensis means "from Canada."
Perennial from a thick rhizome; stem erect, usually simple below, to 15 dm; lower lvs to 5 dm (petiole included), the upper progressively reduced; stipules foliaceous; lfls 7-15, petiolulate, ovate to oblong or elliptic, 3-8 cm, blunt, sharply serrate; spikes 1- several, long-pedunculate, cylindric, 3-12 cm; fls all perfect; hypanthium not roughened between the wings; sep white, elliptic, spreading, 2-3 mm; 2n=56. Marshes, wet meadows, and damp prairies; Nf. and Lab. to Man., s. to N.J., Pa., O., and Ind., and in the mts. to W.Va., Ky. and N.C. July-Sept.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.