Taxonomy
Family: Asteraceae
Habitat
Thrives in disturbed habitats, waste ground. Probably native to floodplains
Associates
Distribution
All of the continental US except NV
Morphology
Herbaceous annual to 2 m or taller. Leaves opposite, simple or palmately 3-5 lobed. Plants monoecious, with the pistillate heads borne below staminate heads in the axils of leaves or bracts. Staminate heads in racemiform inflorescences.
Notes
Flowers late July to September
Wetland Indicator: Facultative +
The pollen of this plant and its congener A. artemisiifolia L. is largely responsible for late summer allergies.
References
Gleason, Henry A.
and A. Cronquist. 1991. Manual of Vascular Plants of Northeastern United States
and Adjacent Canada. Second Ed.
The New York Botanical Garden. Bronx, NY
Swink, F. and G.
Wilhelm. 1994. Plants of the Chicago Region.
Indiana Academy of Science. The Morton Arboretum. Lisle, Illinois.
© Michael Hough 2004 |