Potentilla versicolor |
Potentilla rubricaulis |
|
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Steens Mountain cinquefoil, varying cinquefoil |
red-stem cinquefoil, Rocky Mountain cinquefoil |
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Habit | Plants rosetted to ± matted; taproots ± fleshy-thickened. | |
Caudex branches | not sheathed with marcescent whole leaves. |
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Stems | prostrate to ascending, (0.7–)1.5–2.5(–4) dm, lengths 2–4(–5) times basal leaves. |
ascending to nearly erect, 1.5–4 dm. |
Basal leaves | pinnate with distal leaflets ± confluent, 4–12 × 1–2.5(–3.5) cm; petiole 1–3 cm, straight hairs absent (on early-season petioles) or sparse to common, spreading-ascending to loosely appressed, 1–2 mm, soft, cottony hairs usually absent, glands sparse; primary lateral leaflets 3–5 per side, on distal (1/3–)1/2–2/3 of leaf axis, overlapping, largest ones cuneate to flabellate, 0.5–1.5(–2) × 0.5–1.5 cm, distal 3/4 to whole margin unevenly incised 2/3 to completely to midvein (blade often medially split as well), ultimate teeth or segments 2–5(–8), ± oblanceolate, 3–11 × 1–3 mm, apical tufts to 1 mm, surfaces green to grayish green, not glaucous, straight hairs sparse to common (sparser adaxially), sometimes absent (except on margins), loosely appressed to ascending, 1–2 mm, soft, cottony hairs absent, glands sparse to common. |
often both ternate and palmate on same plant, rarely subpalmate, 4–10 cm; petiole 2.5–7 cm, long hairs sparse to common, loosely appressed to ascending-spreading, 1–2 mm, ± weak to stiff, verrucose, short and/or ± crisped hairs common to abundant, cottony hairs absent, glands usually sparse; leaflets 3–5, proximalmost separated by 0(–1) mm, central oblong to obovate, 1.5–4 × 1–2.5 cm, petiolules 0–5 mm, distal 2/3–3/4 of margin incised 1/2–3/4, rarely +, to midvein, teeth (4–)5–8 per side, 4–5 mm, apical tufts 1 mm, abaxial surfaces gray to grayish white, long hairs abundant, cottony-crisped hairs usually dense, short hairs and glands absent or obscured, adaxial green to grayish green, long hairs sparse to common, 0.5–1.5 mm, stiff, short hairs absent or sparse, rarely common, crisped and cottony hairs absent, glands absent or sparse, rarely common. |
Cauline leaves | 1–2(–3). |
2–3. |
Inflorescences | (1–)3–10-flowered, usually openly cymose. |
4–20-flowered, open, branch angle (10–)20–45°. |
Pedicels | 1–3(–5) cm, straight to slightly recurved in fruit. |
0.5–3 cm, proximal to 5 cm. |
Flowers | epicalyx bractlets lanceolate to elliptic, rarely ovate, 2–5 × 1–2 mm, sometimes apically toothed; hypanthium 3–5 mm diam.; sepals 4–7 mm, apex acute; petals 4–7 × 3–5.5 mm; filaments (1–)1.5–2.5 mm, anthers 0.5–0.8 mm; carpels 10–25, styles 2 mm. |
epicalyx bractlets linear to narrowly lanceolate, 3–4 × 0.8–1.2 mm; hypanthium 4–6 mm diam.; sepals 4–5 mm, apex subacute to acute, glands usually ± sparse, not obscured; petals pale yellow, not overlapping, 5–7 × (4–)5–6.5 mm, distinctly longer than sepals; filaments 0.5–1.5 mm, anthers 0.4 mm; carpels 30–60, styles 0.9–1.1 mm. |
Achenes | 1.5–1.8 mm, smooth to faintly rugose, not carunculate. |
1.2 mm. |
2n | = 56. |
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Potentilla versicolor |
Potentilla rubricaulis |
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Phenology | Flowering summer. | Flowering summer. |
Habitat | Rocky, alpine meadows, seasonally moist slopes, near streams or snowmelt | Sandy lake and stream shores, open sandy forests, dry grassy slopes, sandy and loamy bluffs, rock crevices, scree |
Elevation | 2100–3200 m (6900–10500 ft) | 0–1600 m (0–5200 ft) |
Distribution |
NV; OR
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AK; AB; BC; NT; SK; YT
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Discussion | Potentilla versicolor is most common on Steens Mountain in Harney County, Oregon. Collections are known from other mountain ranges in eastern Oregon (some possibly representing distinct taxa) and from near Island Lake in the Ruby Mountains of northeastern Nevada. The species often grows and, apparently, intergrades with P. breweri; it is usually distinct in its lack of cottony hairs. Petals, filaments, and styles tend to be somewhat shorter in P. versicolor than in P. breweri. Collections of P. versicolor have most often been identified as P. breweri, P. millefolia, or P. ovina. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
As addressed by B. Ertter et al. (2013), the name Potentilla rubricaulis is here restricted to relatively large plants with open inflorescences occurring mainly in glaciated parts of subarctic northwestern Canada and Alaska. Plants from the Chugach Mountains of southern Alaska tend to be more conspicuously glandular than elsewhere. The distinction between Potentilla rubricaulis and large forms of P. arenosa with supernumerary leaflets is problematic. Although both species have somewhat similar petiole vestiture (long, straight, verrucose hairs and a layer of short, stiff, or curly hairs), the latter species tends to have more stiffly spreading petiole hairs and prominently petiolulate central leaflets. The octoploid chromosome count (P. M. Dansereau and E. Steiner 1956) from Great Bear Lake area, Northwest Territories, probably belongs to Potentilla rubricaulis in the narrow sense, since that is its type locality. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 9, p. 171. | FNA vol. 9, p. 207. |
Parent taxa | Rosaceae > subfam. Rosoideae > tribe Potentilleae > Potentilla > sect. Multijugae | Rosaceae > subfam. Rosoideae > tribe Potentilleae > Potentilla > sect. Rubricaules |
Sibling taxa | ||
Synonyms | P. dissecta var. rubricaulis, P. nivea subsp. rubricaulis | |
Name authority | Rydberg: in N. L. Britton et al., N. Amer. Fl. 22: 344. (1908) | Lehmann: Nov. Stirp. Pug. 2: 11. (1830) |
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