Potentilla anglica |
Potentilla plattensis |
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English cinquefoil, potentille d'angleterre, trailing cinquefoil, trailing tormentil, wood cinquefoil |
Platte cinquefoil, Platte River cinquefoil |
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Habit | Plants rosetted to tufted; taproots fleshy-thickened. | |
Stems | soon becoming prostrate, ± flagelliform, usually openly branched, eventually rooting at some nodes, (0.3–)1.5–7+ dm. |
initially decumbent to sometimes ascending, becoming prostrate or supported by vegetation, (0.3–)0.5–3.5(–4.5) dm, lengths 1.5–2.5(–4) times basal leaves. |
Basal leaves | ± persistent, ternate or palmate, 2–10(–12) cm; petiole 1–7(–8) cm, long hairs sparse to abundant, appressed, 0.5–1 mm, stiff, glands absent; leaflets 3–5, central ± obovate to cuneate, 1–3(–3.5) × 0.8–2(–2.5) cm, distal ± 1/2 of margin incised 1/4–1/3(–1/2) to midvein, teeth 2–4 per side, surfaces similar, green, sparsely to moderately hairy. |
pinnate with distal leaflets ± distinct, 2–15(–20) × 1–3 cm; petiole 0.5–5 cm, straight hairs common, tightly appressed, 0.5(–1) mm, stiff, cottony hairs absent, glands absent or sparse; primary lateral leaflets (3–)4–6(–8) per side, on distal (1/4–)1/2–3/4 of leaf axis, overlapping to separate, largest ones obovate, 0.5–1.5(–2) × 0.5–1(–1.3) cm, distal (1/2–)2/3 to whole margin pinnately incised 3/4+ to midvein, ultimate teeth 5–10, linear-oblanceolate, 1.5–8(–10) × 1–2 mm, apical tufts less than 0.5 mm, surfaces green to grayish green, not glaucous, straight hairs sparse to common (sparser adaxially), tightly appressed, 0.5 mm, stiff, cottony hairs absent, glands absent or inconspicuous. |
Cauline leaves | 2–3(–4) proximal to 1st flowering or branching node, usually well expanded at anthesis, usually ternate, 2–6(–10) cm; petiole 0.3–4(–8) cm; leaflets (3–)5, ± resembling or narrower than those of basal leaves, narrowly cuneate, 1–2(–3.5) × 0.8–2(–2.5) cm, apex rounded to obtuse. |
1–3. |
Inflorescences | solitary flowers at stolon nodes. |
(1–)3–15(–20)-flowered, loosely cymose, sometimes racemiform. |
Pedicels | (1–)3–10(–17) cm. |
1–4(–5) cm, ± recurved in fruit. |
Flowers | 4(–5)-merous; epicalyx bractlets narrowly elliptic to oblong or ovate, 3–4(–7) × 1–1.5 mm, smaller than to slightly larger than sepals; hypanthium 2–4 mm diam.; sepals (3–)4–6 mm, apex broadly acute or acuminate; petals 6–9 × 5–9 mm, apex ± retuse; stamens 15–20, filaments 0.8–1.2 mm, anthers 0.8–1.2 mm; carpels 20–50, styles 0.9–1.5 mm. |
epicalyx bractlets narrowly elliptic to linear-lanceolate, 2–5(–6) × 0.5–2 mm; hypanthium 3–4 mm diam.; sepals 3–6 mm, apex acute; petals 4–7 × 3–6 mm; filaments 1–2.5 mm, anthers 0.5–1 mm, usually ± 1/2 as long as filaments; carpels 10–20, styles 1.5–2.5 mm. |
Achenes | 1–1.5(–1.8) mm, ± smooth. |
(1.3–)1.5–1.9 mm, smooth, often ± carunculate. |
Rootstocks | ± erect, stout to slender, 1–4 cm. |
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2n | = 28, 56 (Europe). |
= 70. |
Potentilla anglica |
Potentilla plattensis |
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Phenology | Flowering May–Aug(–Nov). | Flowering summer. |
Habitat | Moist flats and slopes, mainly on acidic soil | Moist meadows, streamsides, reservoir margins |
Elevation | 0–1200 m (0–3900 ft) | 300–2900 m (1000–9500 ft) |
Distribution |
CA; CO; ME; NY; OR; PA; UT; WA; BC; NL; NS; QC; SPM; Europe [Introduced in North America; introduced also in Atlantic Islands (Azores, Madeira), Pacific Islands (New Zealand), Australia]
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AZ; CO; ID; MT; ND; NM; SD; UT; WY; AB; MB; NT; SK
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Discussion | Potentilla anglica apparently is a product of hybridization involving P. erecta and P. reptans (B. Matfield and J. R. Ellis 1972) that has become stabilized and distinct from both parents. In Europe, it forms back-cross hybrids with both P. erecta (P. ×suberecta Zimmeter) and P. reptans (P. ×mixta Nolte); these hybrids are not known from North America. A garden hybrid supposedly between P. anglica and P. nepalensis Hooker (known as P. ×tonguei Mallett) was found in Allegany State Park, New York, but this was likely cultivated rather than naturalized. Potentilla anglica probably was introduced even in Newfoundland (A. Kurtto et al. in J. Jalas et al. 1972+, vol. 13), contrary to the view expressed by M. L. Fernald (1950). The name Potentilla procumbens Sibthorp was previously used for this species; that is a superfluous and illegitimate name. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Potentilla plattensis occurs mostly east of the Continental Divide from the Canadian Prairies to the mountains of New Mexico. The species barely enters Idaho at Monida Pass (Clark County). Populations also exist in the White Mountains of east-central Arizona and the mountains of southern Utah. The species is relatively uniform throughout its range but there is often significant seasonal variation, such that plants can be compact and densely strigose in early summer but elongate and subglabrous later in the season. Where the ranges of Potentilla plattensis and P. ovina overlap, the two are sometimes difficult to distinguish. The habitats are usually distinct, in that P. plattensis generally occurs in moist valley bottoms and P. ovina occurs in rocky uplands. Differences in vestiture are also diagnostic: hairs of P. plattensis are 0.5 mm and tightly appressed; those of P. ovina are longer and looser. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 9, p. 135. | FNA vol. 9, p. 173. |
Parent taxa | Rosaceae > subfam. Rosoideae > tribe Potentilleae > Potentilla > sect. Potentilla | Rosaceae > subfam. Rosoideae > tribe Potentilleae > Potentilla > sect. Multijugae |
Sibling taxa | ||
Synonyms | P. diversifolia var. madsenii, P. plattensis var. pedicillata | |
Name authority | Laicharding: Veg. Europ. 1: 475. (1790) | Nuttall: in J. Torrey and A. Gray, Fl. N. Amer. 1: 439. (1840) |
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