Symphyotrichum undulatum perennial 30-120 cm tall from a branched root crown, usually densely fine-hairy.
Leaves alternate, 3.5-14 cm long, 1.5-7 cm wide, variable, lower leaves with lobed base, stalked, base of stalk usually wide, lobed and clasping stem, margins wavy, upper leaves often stalkless, clasping at base.
Flowers: rays blue-lilac, 10-20, bracteate base of flower head 0.4-0.7 cm long, bracts overlapping, tips sharply pointed, Aug.-Nov.
Fruit dry, 1-seeded, achene, with tuft of hairs (pappus), wind dispersed.
Wetland status: UPL.
Frequency in NYC: Very infrequent.
Habitat: Dry, open woods.