Potentilla simplex |
Potentilla lasiodonta |
|
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common cinquefoil, old-field cinquefoil, old-field five-fingers, potentille simple, simple cinquefoil |
Sandhills cinquefoil |
|
Stems | initially erect to ascending to 5 dm, then arching above ground-level, becoming prostrate, flagelliform, not branched, rooting at distal nodes, (0.5–)1.5–12 dm. |
± erect, 2–4 dm. |
Basal leaves | persistent or ephemeral, usually palmate, 3.5–20 cm; petiole 1–15 cm, long hairs ± abundant, appressed to spreading, (0.5–)1–3 mm, weak to ± stiff, glands absent or sparse, sometimes common; leaflets 5(–7), central narrowly elliptic to obovate, 1.5–5 × 0.5–2.5 cm, distal 1/2–3/4 of margin incised 1/4–1/3 to midvein, teeth 4–8(–13) per side, surfaces similar to ± dissimilar, abaxial green to silvery white, sparsely to abundantly hairy, adaxial green, glabrate or sparsely to moderately hairy. |
pinnate, 12–20(–30) cm; petiole 5–10(–15) cm, long hairs ± abundant, spreading to ascending, 0.5–1 mm, weak to ± stiff, short hairs abundant to dense, cottony or crisped hairs absent, glands sparse to abundant, often obscured; leaflets 4–6(–9) per side, on distal (1/3–)1/2–3/5 of leaf axis, slightly overlapping, terminal ones oblanceolate to narrowly elliptic, 3–6 × 0.8–1.2(–1.5) cm, margins strongly revolute, incised ± 1/2 to midvein, undivided medial blade 5–9 mm wide, teeth 8–12 per side, narrowly triangular to lanceolate, surfaces ± dissimilar, abaxial grayish, long hairs ± sparse (or not differentiated from short hairs), 0.5–1.5 mm, weak, short hairs abundant to dense, cottony or crisped hairs absent, glands sparse or obscured, adaxial ± green, straight hairs (long and short not differentiated) abundant, spreading to ascending, 0.2–0.5 mm, cottony and crisped hairs absent, glands sparse to abundant, often obscured. |
Cauline leaves | (0–)1 proximal to 1st flowering node, well expanded at anthesis, usually palmate, 2.5–6(–9) cm; petiole 0–2(–4) cm; leaflets (3–)5, often more elongate than those of basal leaves, ± elliptic to oblanceolate, sometimes obovate, 1.5–6(–7.5) × 0.5–2(–3) cm, apex acute to obtuse. |
(1–)2–4. |
Inflorescences | solitary flowers at stolon nodes. |
10–40-flowered, congested or elongating in fruit. |
Pedicels | 1–5(–8.5) cm. |
± 0.1 cm (proximal to 1.2 cm). |
Flowers | 5(–6)-merous; epicalyx bractlets linear to narrowly lanceolate, 2–5 × 1–1.5(–2) mm, often larger than sepals (especially in bud); hypanthium 3–5 mm diam.; sepals 4–6 mm, apex broadly acute; petals 4–7 × 3–6 mm, apex rounded to ± retuse; stamens ca. 20, filaments 0.5–2 mm, anthers 0.6–1 mm; carpels 20–50, styles 0.8–1.5 mm. |
epicalyx bractlets narrowly ovate-acuminate, (3–)4–8(–10) × 2–3 mm, lengths 1–2 times sepals, margins ± revolute; hypanthium (4–)5–10 mm diam.; sepals 3–5 mm, apex acute to obtuse, abaxial surfaces: venation moderate, glands ± abundant, obscured to evident; petals pale yellow, 3–5 × 2–4 mm, lengths ± equal to or shorter than sepals; filaments 1–1.5 mm, anthers 0.5–0.8 mm; carpels 80–90, styles papillate-swollen in proximal 3/4+, 1–1.2 mm. |
Achenes | 0.9–1.2 mm, faintly rugose. |
± 1 mm, ± rugose. |
Rootstocks | horizontal, irregularly thickened or moniliform, 1–8 cm. |
|
2n | = 14. |
|
Potentilla simplex |
Potentilla lasiodonta |
|
Phenology | Flowering (Mar–)Apr–Jul(–Aug). | Flowering summer. |
Habitat | Dry or infrequently moist flats and slopes in pastures, dry meadows, roadsides, old fields, edges of mixed oak and conifer woodlands, often on acidic soil | Sandy sites in prairies |
Elevation | 0–800 m (0–2600 ft) | 300–1100 m (1000–3600 ft) |
Distribution |
AL; AR; CT; DC; DE; GA; IA; IL; IN; KS; KY; LA; MA; MD; ME; MI; MN; MO; MS; NC; NE; NH; NJ; NY; OH; OK; PA; RI; SC; TN; TX; VA; VT; WI; WV; NB; NF; NS; ON; PE; QC; SPM
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MN; ND; AB; MB; SK |
Discussion | The distinction between Potentilla simplex and P. canadensis is subtle, and the former is often misidentified as the latter; additional features to distinguish the two species are provided by M. L. Fernald (1931). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Potentilla lasiodonta is a diploid relative of tetraploid P. pensylvanica, sharing similar velvety vestiture of dense short hairs, pinnate leaves, and epicalyx bractlets with revolute margins. The species differs in having larger epicalyx bractlets and less deeply incised leaflets. Plant height and leaf size are at the upper range of P. pensylvanica, and populations are evidently restricted to sandy substrates. Occurrence in Manitoba is based on B. L. Kohli and J. G. Packer (1976); no vouchers are in WIN. At least one collection from southeastern British Columbia (Brown 779, MO) approaches P. lasiodonta, but it is insufficient by itself to serve as a provincial record. The fundamental ploidy and epicalyx distinctions of this species were established by B. L. Kohli and J. G. Packer (1976), who proposed the name Potentilla finitima. As noted by J. Soják (1994), the type of P. lasiodonta is the same entity. Potentilla atrovirens Rydberg and P. pensylvanica var. arida B. Boivin have sometimes been applied to this taxon; the types of both names fall within the circumscription of P. pensylvanica in the narrow sense (Packer, pers. comm.). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 9, p. 134. | FNA vol. 9, p. 214. |
Parent taxa | Rosaceae > subfam. Rosoideae > tribe Potentilleae > Potentilla > sect. Potentilla | Rosaceae > subfam. Rosoideae > tribe Potentilleae > Potentilla > sect. Pensylvanicae |
Sibling taxa | ||
Synonyms | P. canadensis var. simplex, P. simplex var. argyrisma, P. simplex var. calvescens | P. finitima |
Name authority | Michaux: Fl. Bor.-Amer. 1: 303. (1803) | Rydberg: in N. L. Britton et al., N. Amer. Fl. 22: 351. (1908) |
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