Aster laevis L.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
Species Description - Plants 3–10 dm from a short, stout rhizome or branched caudex, sometimes with short, slender, creeping red rhizomes as well; herbage glabrous except occasionally for some puberulent lines in the infl, commonly ± glaucous; lvs mainly cauline, thick and firm, highly variable in size and shape, but the larger ones more than 1 cm (often more than 2.5 cm) wide and often less than 5 times as long as wide, entire or sometimes toothed, sessile and ± strongly auriculate-clasping, the lower tapering to a winged petiole and scarcely clasping, those of the infl reduced and often bract-like, broadest at the clasping or subclasping base; heads several or many in an open infl; invol 5–9 mm, its firm, appressed, acute bracts conspicuously imbricate in several series, with short, diamond-shaped green tip mostly 1–2 mm; rays 15–30, blue or purple, 8–15 mm; achenes glabrous or nearly so; pappus usually reddish; 2n=48. Open, usually dry places; Me. to B.C., s. to Ga., Ark., and N.M. Most of our plants are var. laevis, as described above. The western var. geyeri A. Gray, with the invol bracts fewer-seriate, narrower, and more sharply pointed, their green tips more elongate, extends into our range from Minn. to Mo. (A. geyeri; A. laeviformis)