From Flora of Indiana (1940) by Charles C. Deam

Infrequent in the unglaciated region on barren wooded slopes and appearing again in the northern counties in a dry, sandy, prairie habitat.

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Indiana Coefficient of Conservatism: C = 8

Wetland Indicator Status: N/A

Diagnostic Traits: Coarse perennial to 2 m tall; stems hollow, finely pubescent; leaves 2-3 ternately compound, leaflets obtuse, petiolar sheaths expanded; umbel globose, to 15 cm wide; flowers white; fruits sparsely pubescent. 

Stout, to 2 m, becoming tomentulose-canescent in the infl; principal lvs long-petioled, 1-2 dm, the upper reduced, with sheathing petioles; lfls oblong to elliptic, varying to lanceolate, 2-4 cm, obtuse, finely serrate; umbels 5-15 cm wide, rays 18-35; pedicels and ovary pubescent; fr oblong-elliptic, 4-7 mm, cordate at base, sparsely pubescent along the wingless dorsal ribs; lateral ribs winged; oil-tubes few; seed adherent to the pericarp; 2n=22. Dry woods and thickets; Mass. to Minn., s. to Fla., Miss., and Ark. July-Aug. (A. villosa Walter, not Lag.)

Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.

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