Ranunculus canus

Bentham

Pl. Hartw., 294. 1849.

Endemic
Treatment appears in FNA Volume 3.

Stems erect to decumbent, never rooting nodally, hirsute, pilose, or glabrous, base not bulbous. Roots never tuberous. Basal leaf blades ovate to narrowly ovate in outline, 3-parted or -foliolate, 3.3-9.5 ×3.5-9.4 cm, leaflets or segments 1-3×-lobed, ultimate segments ovate or oblong-ovate to lanceolate, margins toothed, apex acute or obtuse. Flowers: receptacle glabrous; sepals reflexed 1-2 mm above base, 3-8 × 2-4 mm, hirsute; petals 5-17, yellow, 6-12 × 3-6 mm. Heads of achenes hemispheric to globose, 6-9 × 7-10 mm; achenes 3.4-4.4 × 2.4-3.6 mm, glabrous or rarely hispid, margin forming narrow rib 0.1-0.2 mm wide; beak persistent, deltate or lance-deltate, curved, 0.2-1.2 mm.

Discussion

Varieties 2 (2 in the flora).

Ranunculus canus intergrades with R. occidentalis var. occidentalis and R. californicus, and some populations can be difficult to assign to species. The deltate or lance-deltate achene beak of R. canus, however, which is usually 0.8-1.2 mm wide at the base and less than 1.5 times as long as wide, contrasts with the narrower beaks of the other two species, which are usually less than 0.6 mm wide and at least twice as long as wide.

Selected References

None.

Key

1 Petals 5–7; Sacramento Valley and adjacent foothills. Ranunculus canus var. canus
1 Petals 13–17; Transverse Ranges. Ranunculus canus var. ludovicianus