Erigeron bonariensis
Hairy Fleabane or Flax Leaved Horseweed
Family: Asteraceae, Place of Origin: South America
Hairy fleabane is aptly named: it is strigose (set with stiff bristles or hairs) throughout the plant – stems, leaves, flowers.
Hairy fleabane is an low annual, (about 8″ to 3′) and thrives in disturbed areas. I’ve seen it emerge in cracks in pavement and in areas formerly occupied by European beachgrass in the Dunes. Often, it is present with Erigeron canadensis (Horseweed), which is native to North America. Horseweed, along with another native composite, Heterotheca grandiflora (Telegraph weed) are the most unattractive weedy natives in California.
Hairy fleabane produces many urn or barrel shaped flowers, the fluffy seeds are sandy colored and distributed by the breeze. In the Dunes it is competing with other composites such as Dunedelions and Cudweeds and should be removed.
Mark Skinner