Coarse, erect perennial to 1 m or more from fascicled roots, usually simple to the infl; lvs linear, much elongate, parallel-veined, entire or remotely spinulose, the lower to 8 dm × 3 cm, the upper gradually reduced; heads round-ovoid, 1-2 cm long and thick; bracts lance-ovate, entire or nearly so, cuspidate, rarely projecting from beneath the head; bractlets similar but smaller; 2n=96. Moist or dry sandy soil, open woods, and prairies; s. U.S., n. to Va., Ind., Minn., and Kans., and occasionally adventive farther north. July, Aug. (E. aquaticum, misapplied)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
Infrequent to frequent in moist sandy soil in prairie habitats in northwestern and western Indiana and in the southern counties in dry oak woods which, for the most part, were formerly known as the barrens.
Indiana Coefficient of Conservatism: 10
Wetland Indicator Status: FAC
Diagnostic Traits: coarse perennial; leaves simple, linear (to 3 cm wide) with finely spinulose margins; inflorescences umbelliform or corymbiform with several spinulose-bracted heads; flowers white, sessile.