Plants 10–100+ cm.
Leaves 5–25 cm.
calyculi 5, ovoid to deltate.
Involucres 12–15 mm.
Phyllaries abaxially bristly.
Florets 20–40+; ligules 15–20 mm, yellow, often reddish abaxially.
Fruits bodies 2.5–3 mm, reddish brown or outermost pale tan; beaks 2.5–4 mm.
2n=10.
Roadsides, disturbed areas. Flowering Jun–Sep. 0–600 m. CR, Sisk, WV. CA; widely scattered in North America; Europe. Exotic.
This species’ roadside habit may encourage further spreading to other parts of the state.
as described under Helminthotheca echioides
Leaf blades 50-150(-250) × 10-50(-80+) mm. Peduncles 1-5+ cm, bristly hispid. Calyculi: bracts 9-15+ × 3-5+ mm, margins and tips bristly-ciliate. Phyllaries often sigmoid in fruit, abaxial faces and tips bristly. Cypselae: bodies 2.5-3 mm, beaks 2.5-5 mm; pappi 4-7 mm. 2n = 10.Flowering May-Nov. Disturbed sites; 0-50(-500) m; introduced; Alta., N.B., Ont., Sask.; Ariz., Calif., Conn., D.C., Iowa, Maine, Md., Mass., Mo., Mont., N.J., N.Y., N.Dak., Ohio, Oreg., Pa., Vt., Va.; Europe; widely introduced elsewhere.Reports for British Columbia and Nova Scotia need confirmation.