Stem generally glabrous or nearly so, sometimes spreading-hairy toward the base; most of the lvs, except for a few upper ones, generally ±evidently wing-petiolate, the lower surface glabrous or short-hairy, seldom any of the hairs as much as 1 mm; head with mostly 16-35 (commonly ca 21 or 34) rays; invol bracts glabrous except for the ciliate margins; widespread, mainly to the w. or n. of var. connatum.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
Found throughout the state although it may be absent from a few of our northern counties. It is generally found on the alluvial banks of streams and on the low borders of lakes. It is found both in woodland and in open places and sometimes in low ground along roadsides.