General: Perennial (or annual) herb from thick and somewhat fleshy root mass; stems from nearly erect to prostrate, often rooting at nodes, 20-90 cm long, long-hairy or smooth, hollow.
Leaves: Basal, persistent, heart- to kidney-shaped, 3-parted, the blades 3.5-8 cm long, 4.5-9.5 cm wide, the leaflets 3-lobed or -parted, the ultimate segments elliptic or lance-elliptic, toothed or shallowly lobed, tips pointed, the leaf stalks to 30 cm long, the stalks of lateral leaflets 3-10 mm long; stem leaves 1 or 2 and transitional to much-reduced bracts.
Flowers: Inflorescence of few-flowered, terminal cymes, the flower stalks to 6 cm long; receptacle long-hairy; petals 5, distinct, yellow, 4-6 mm long, 3.5-5 mm wide, egg-shaped, nectary on upper surface, the scale about 0.5 mm long, smooth; sepals 5, spreading or bent back about 1 mm above base, soon deciduous, 4-6 mm long, 1.5-3 mm wide, smooth or long-hairy; stamens 20-40; pistils 20-60.
Fruits: Achenes, numerous in a globe- to egg-shaped head 7-11 mm long, 7-10 mm wide, the achenes elliptic to egg-shaped, 2.4-3 mm long, 2-2.4 mm wide, smooth, margins slightly keeled; beaks persistent, lanceolate, 1-1.2 mm long, straight or nearly so.
Notes: The smooth to nearly smooth form (var. oreganus) has been collected on occasion in BC but does not warrant formal recognition.
Wet to moist meadows, shores, ditches, streambanks, thickets and forest openings in the lowland, steppe and montane zones; common throughout BC except rare near the coast; N to AK, YT and NT, E to NF and S to MI, MN, NE, NM, AZ, NV and N CA.
The table below shows the species-specific information calculated from original data (BEC database) provided by the BC Ministry of Forests and Range. (Updated August, 2013)