Perennial from a stout taproot and often a branched caudex, decumbent to erect, 2–8 dm, the stem thinly to densely tomentose; lvs pinnately compound, glabrous to sericeous above, subglabrous to white-tomentose beneath, the lower long-petioled, the cauline progressively reduced and less petioled or subsessile; lfls 5–13 (+), or 3 in smaller lvs, the upper 3 approximate and often confluent, oblanceolate to obovate, deeply toothed or cleft; stipules of the cauline lvs commonly laciniate; infl usually a compact cyme, seldom over 5 cm wide; pet yellow; style 1 mm, terminal, thickened and glandular at base; 2n=14, 28, 56. A polymorphic sp. of n. and w. N. Amer. and much of temperate and boreal Eurasia, often divided into a number of spp. or infraspecific taxa. Our plants can be sorted into 3 morphologically confluent but cytologically apparently distinctive vars.
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