Potentilla bipinnatifida |
Potentilla sterilis |
|
---|---|---|
bipinnate cinquefoil, potentille bipinnatifide, tansy cinquefoil |
strawberry leaf cinquefoil or barren-strawberry, strawberryleaf cinquefoil |
|
Stems | ascending to erect, (1–)2–5 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. |
petiole 2–7(–17) cm, long hairs common to abundant, 1–2 mm; central leaflets (0.8–)1.5–3(–5) × (0.6–)1–2(–3) cm, straight hairs common to abundant (sparser adaxially), glands absent or sparse. |
Cauline leaves | 2–4. |
|
Inflorescences | (4–)10–50(–100)-flowered, congested or elongating in fruit. |
|
Pedicels | 0.2–0.8 cm (proximal to 2 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 ± lanceolate, 2.5–4 × 0.8–1.3 mm; sepals 4–6.5 mm, apex ± acute; petals 4–7 × 3–5 mm; filaments 0.8–2 mm, anthers 0.6–0.9 mm; carpels numerous. |
Achenes | 1–1.2 mm, smooth to faintly rugose. |
1.5 mm. |
2n | = 56. |
= 28 (Europe). |
Potentilla bipinnatifida |
Potentilla sterilis |
|
Phenology | Flowering summer. | Flowering spring. |
Habitat | Open shortgrass prairie, alkaline bottoms, streamsides in sagebrush, disturbed sites | Dry to moist, often rocky slopes |
Elevation | 10–3400 m (0–11200 ft) | 0 m (0 ft) |
Distribution |
AK; CO; ID; MI; MN; MT; ND; NE; NM; SD; UT; WY; AB; MB; NT; ON; QC; SK; YT
|
NF; Europe [Introduced in North America] |
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 sterilis was collected from the coast of Newfoundland in 1928 (A. M. Ayre s.n., GH); no recent documentation of occurrence is known (J. Maunder, pers. comm. to L. Brouillet). Although previously treated as native (M. L. Fernald 1950; E. Hultén and M. Fries 1986), this status has been challenged (for example, A. Kurtto et al. in J. Jalas et al. 1972+, vol. 13). According to H. A. Gleason and A. Cronquist (1991), the species is also rarely introduced in the eastern United States; no vouchers have been seen. Potentilla sterilis is superficially similar to strawberry (Fragaria) but lacks the fleshy fruit; other differences include stolon structure, anther morphology, and style length and attachment. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 9, p. 217. | FNA vol. 9, p. 132. |
Parent taxa | Rosaceae > subfam. Rosoideae > tribe Potentilleae > Potentilla > sect. Pensylvanicae | Rosaceae > subfam. Rosoideae > tribe Potentilleae > Potentilla > sect. Lupinoides |
Sibling taxa | ||
Synonyms | P. pensylvanica var. bipinnatifida | Fragaria sterilis |
Name authority | Douglas: in W. J. Hooker, Fl. Bor.-Amer. 1: 188. (1832) | (Linnaeus) Garcke: Fl. N. Mitt.-Deutschland ed. 4, 112. (1858) |
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