Symphyotrichum pilosum var. pilosum

General:
Perennial herb from a stout, woody stem-base; stems erect, branched above, glabrous or sometimes soft-hairy, 0.1-1.5 m tall.

Leaves:
Basal leaves soon deciduous; stem leaves soon deciduous below, middle ones oblanceolate, stalked, 5-10 cm long, 1-2 cm wide, upper ones linear to lance-elliptic, unstalked or nearly so, entire or slightly toothed, glabrous to hairy, becoming reduced upward and awl-shaped.

Flowers:
Heads with ray and disk flowers, few to more usually numerous in an often diffuse inflorescence, sometimes one-sided on the branches; involucres 3.5-8 mm tall; involucral bracts subequal or graduated, with a loose, awl-shaped, marginally inrolled, green tip; ray flowers 16-35, white or sometimes pink or purple, 5-10 mm long; disk flowers yellow.

Fruits:
Achenes about 1 mm long, hairy; pappus of numerous white, hairlike bristles.

Source:  The Illustrated Flora of British Columbia