Vasilis Teodoridis:
Asteraceae
Whiteweed Aster is a perennial erect herb with long rhizomes. Stems are cylindrical; 1-4 ft tall; branching upward. Stem leaves are distinctly 3-nerved; nearly hairless or scarcely hairy on both surfaces; middle leaves 4-12 cm long; 2-4 cm broad; ovate-oblong or oblong-lanceolate; tip tapering; base sharply narrowed; wedge-shaped. The leaves are either stalkless or short-stalked; with margins serrate with 4-8 pairs of shallow teeth; upper leaves are smaller. Flower-heads are few to numerous in loose corymbs; 1.5-2 cm across; stalk 2-10 mm long. Ray florets are 10-15 or more; white; rarely purple; 5-8 mm long; 0.8-1.4 mm wide. Disc florets are yellow. Pappus is dirty white or reddish; 4-5 mm long at maturity. Flowering: September-February.