Erigeron bonariensis

Flax-leaved horseweed

Family: Asteraceae · Type: annual · Not Native

Flax-leaved horseweed is a naturalized annual herb found in northern California regions including the Central Valley, Coast Ranges, Sierra Nevada foothills, and desert mountains at elevations up to 1,300 meters. Flowering throughout the year, this plant produces white to green-white and purple flowers in small disciform heads arranged in raceme-like clusters. Growing with erect or ascending stems 10 to 100 centimeters tall, densely covered in gray hairs and becoming branched towards the top. Its leaves range from oblanceolate basal leaves up to 8 centimeters long and 25 millimeters wide to narrow linear distal leaves 1 to 5 centimeters long. The fruit is pale tan, with 15 to 25 cream-colored pappus bristles 3 to 4 millimeters long.

Habitat: Disturbed sites

Bloom period: All year

Elevation: < 1300+ m

Bioregions: NCoRI, CaRF, n&ampc SNF, GV, CW, SW, DMtns

Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Jepson eFlora, Cal-IPC, and more.