Symphyotrichum ericoides 

or White Heather Aster

Perennial herb from a fibrous-rooted short rhizome or branched, woody stem-base; stems ascending, much branched and hairy above, 30-200 cm tall. Heads with ray and disk flowers, usually numerous in a branched open inflorescence, tending to become one-sided on the recurving branches. Mesic to dry grasslands, shrublands, alkaline flats, rocky slopes, disturbed areas and open forests in the lowland, steppe and montane zones.