Taxonomy
Family: Asteraceae
Habitat
Fields, waste places, woods.
Associates
Distribution
Quebec and Prince Edward Island to Saskatchewan, south to FL and TX.
Morphology
Herbaceous biennial, sometimes annual; stems 0.3-2.5 m, glabrous or coarsely hirsute, often more or less glaucous; leaves variable, entire or toothed to pinnately lobed or cleft, sagittate or sometimes narrowed to the base, to 35 cm long; heads numerous, small, with 13-22 yellow flowers; involucres 10-15 mm in fruit; achenes blackish, very flat, with a median nerve on each face, transversely rugulose, 4.5-6.5 mm total length, the slender beak from a little more than half to about as long as the body; mature pappus 5-7 mm.
Notes
Flowers July to September
Wetland indicator: FACU
Differs from other species with small flower heads (involucres 10-15 mm in fruit) in having a single median nerve on each face of the achene.
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.
Michael Hough © 2018 |