Syn.: Thaspium trifoliatum var. apterum A. Gray, Zizia cordata W. D. J. Koch ex DC.
Family: Apiaceae Lindl.
Distribution: North American species found in Appalachian mountains, in northern prairie and Rocky Mountains. Doesn’t reach extreme north.
Ecology: It grows in the prairie and woodlands, on banks of rivers. It blooms from May to July.
Description: Perennial herb, stems clustered, 20–60 cm tall, hollow, hairless, from fleshy, clustered, fibrous roots. Basal leaves are heart-shaped 2–10 cm long, toothed, long stalked; stem leaves few, short-stalked, once or twice divided in threes, toothed. Flowers are yellow, very small, in dense twice-divided, flat topped clusters (umbels) 1.5–4 cm across and without bracts at base. Fruits are oblong schizocarps about 3 mm long, hairless with prominent ribs.
Threat and protection: American states of Connecticut, Indiana and Michigan list this plant in various risk categories.
Note: The genus was named after a German botanist Johann Baptist Ziz (1779–1829) and is applied to 3 north-american species.
These images were taken in Canada, Alberta, Calgary, Bowmont Park (June 2011).
