Crooked-stem Aster
Symphyotrichum prenanthoides (Muhl.) Nesom occurs in moist or swampy grounds, woods, thickets, meadows, seeps, stream banks, roadsides in southern Ontario and the northern states in the eastern US and further south in the mountains and disjunct in southwestern Wisconsin and adjacent states (Brouillet et al. 2006; ). Stems are usually flexuous and the serrate leaf blade narrowed below the mid point and the base is flared and clasping the stem. Rays are usually lavender to blue, rarely white. Symphyotrichum prenanthoides is of conservation concern in Canada and in a number of states. The species is tetraploid (2n=32).
Last revised 13 May 2025 by J.C. Semple
© 2025 J.C. Semple, including all photographs unless otherwise indicated
1-2. Symphyotrichum prenanthoides. 1. Inflorescence, West Virginia. 2. Clasping stem leaf.Â
Brouillet, L., J.C. Semple, G.A. Allen, K. Chambers and S. Sundburg. 2006.  Symphyotrichum Nees. pp. 465-539. In Flora North America Editorial Committee, eds. Flora of North America. Vol. 20. Asteraceae, Part 2. Astereae and Senecioneae. Oxford University Press, New York.