Potentilla bipinnatifida |
Potentilla pulchella |
|
---|---|---|
bipinnate cinquefoil, potentille bipinnatifide, tansy cinquefoil |
potentille jolie, pretty cinquefoil |
|
Stems | ascending to erect, (1–)2–5 dm. |
ascending, 0.1–1.5(–2) dm. |
Basal leaves | subpinnate to subpalmate, (6–)10–25 cm; petiole (2–)5–15 cm, long hairs dense, appressed, 1–2 mm, soft to ± stiff, short hairs absent, crisped hairs sparse, glands absent, sparse, or obscured; leaflets 2–3 per side, on distal 1/6–1/3(–1/2) of leaf axis, separate to ± overlapping, terminal ones oblanceolate, (2–)3–6(–10) × 1–2(–3.5) cm, margins revolute, incised 3/4+ to midvein, undivided medial blade 1.5–6 mm wide, teeth 5–8 per side, ± linear, surfaces ± to strongly dissimilar, abaxial usually white, rarely grayish, long hairs abundant especially on veins, 1–2 mm, ± weak, short hairs absent or obscured, cottony (and crisped) hairs ± dense, glands absent or obscured, adaxial green to grayish, long hairs sparse to abundant, loosely appressed, 0.5–1.5 mm, short hairs absent or sparse, crisped and/or cottony hairs sparse to common, glands sparse to common. |
subpinnate, 1.5–9 cm; petiole 0.7–4 cm, long hairs common to dense, ± appressed to ascending, 0.5–3 mm, soft, short hairs absent, crisped hairs sparse to abundant, glands absent or sparse; leaflets (1–)2(–3) per side, on distal 1/6–1/2 of leaf axis, separate to overlapping, terminal ones oblong or obovate, 0.4–3 × 0.2–1.2 cm, margins revolute, incised 2/3–3/4+ to midvein, undivided medial blade 2–6 mm wide, teeth 2–5 per side, linear to narrowly oblong, surfaces dissimilar, abaxial white, long hairs ± abundant, 1–2 mm, soft, short hairs absent or obscured, crisped and/or cottony hairs dense, glands absent or obscured, adaxial grayish white to dark grayish green, long hairs sparse to dense, loosely appressed to spreading, 0.5–2 mm, short hairs absent, crisped hairs absent or sparse, glands absent. |
Cauline leaves | 2–4. |
1–2. |
Inflorescences | (4–)10–50(–100)-flowered, congested or elongating in fruit. |
(1–)2–5(–9)-flowered, ± open. |
Pedicels | 0.2–0.8 cm (proximal to 2 cm). |
0.5–1 cm (proximal to 5 cm). |
Flowers | epicalyx bractlets narrowly elliptic to lanceolate, 2.5–6 mm, lengths ± 2/3 times sepals, margins flat; hypanthium 3–5 mm diam.; sepals 3–6 mm, apex ± acute, abaxial surfaces: venation indistinct, glands absent, sparse, or obscured; petals yellow, 3–5 × 3–4 mm, lengths ± equal to sepals; filaments 0.5–2 mm, anthers 0.3–0.5 mm; carpels 50–80, styles papillate-swollen in proximal 1/2–3/4+, 1–1.2 mm. |
epicalyx bractlets oblong to ovate, 2–4(–6) × 0.8–1.3(–2) mm, lengths ± 3/4 times sepals, margins sometimes revolute; hypanthium 2.5–4 mm diam.; sepals 3–5 mm, apex obtuse to subacute, abaxial surfaces: venation indistinct, glands ± abundant, often obscured; petals pale yellow, 4–5 × 2–3 mm, lengths 1.5 times sepals; filaments 1–1.5 mm, anthers 0.4 mm; carpels 30–60, styles papillate-swollen in proximal 1/4–1/3, 0.9–1.2 mm. |
Achenes | 1–1.2 mm, smooth to faintly rugose. |
1.4–1.5 mm, smooth or rugose. |
2n | = 56. |
= 28. |
Potentilla bipinnatifida |
Potentilla pulchella |
|
Phenology | Flowering summer. | Flowering summer. |
Habitat | Open shortgrass prairie, alkaline bottoms, streamsides in sagebrush, disturbed sites | Dry or damp, open tundra, silt flats, stream and seashore banks, bird cliff meadows, fine scree, on loam, clay, or calcareous substrates |
Elevation | 10–3400 m (0–11200 ft) | 0–600 m (0–2000 ft) |
Distribution |
AK; CO; ID; MI; MN; MT; ND; NE; NM; SD; UT; WY; AB; MB; NT; ON; QC; SK; YT
|
AK; MB; NL; NT; NU; ON; QC; YT; Greenland; Eurasia |
Discussion | Potentilla bipinnatifida is similar to P. litoralis in habit and leaf dissection but has flat, silky epicalyx bractlets and sepals with no evident glands. Vestiture is generally silkier, and the silvery to bicolor leaves are white-cottony abaxially. The two species are sympatric in the plains of Canada, with some intergradation; P. bipinnatifida is also common south to Colorado, where it is found in intermontane meadows and sagebrush flats. Outlying populations occur in Blaine and Custer counties, Idaho, and Duchesne and Piute counties, Utah. Eastern collections from disturbed sites might be adventive. Potentilla missourica Hornemann ex Lindley and P. normalis Besser ex Sprengel are older names for this species; both were rejected against a conserved P. bipinnatifida with designated lectotypes (see J. Soják 2008b). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Potentilla pulchella is morphologically isolated within sect. Pensylvanicae and is very polymorphic. The proposed races (var. elatior, subsp./var. gracilicaulis) differ only in characters appearing throughout the range of the species (more slender and erect to ascending stems, less hairy leaves). Some different morphs are often found close together but in different habitats. Some species with palmate or subpalmate leaves combine features of Potentilla pulchella and species from sect. Niveae (addressed under 8t. sect. Rubricaules); others are possible hybrids between P. hyparctica and P. pulchella (sect. Aureae). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 9, p. 217. | FNA vol. 9, p. 217. |
Parent taxa | Rosaceae > subfam. Rosoideae > tribe Potentilleae > Potentilla > sect. Pensylvanicae | Rosaceae > subfam. Rosoideae > tribe Potentilleae > Potentilla > sect. Pensylvanicae |
Sibling taxa | ||
Synonyms | P. pensylvanica var. bipinnatifida | P. pulchella var. elatior, P. pulchella subsp. gracilicaulis, P. pulchella var. gracilicaulis, P. usticapensis |
Name authority | Douglas: in W. J. Hooker, Fl. Bor.-Amer. 1: 188. (1832) | R. Brown: Chlor. Melvill., 19. (1823) |
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