Potentilla versicolor |
Potentilla arenosa |
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Steens Mountain cinquefoil, varying cinquefoil |
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Habit | Plants rosetted to ± matted; taproots ± fleshy-thickened. | Plants scarcely to ± tufted. | ||||
Caudex branches | thick, not columnar, 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 erect, (0.3–)0.8–2.5(–4.5) dm, lengths (2–)3–5 times basal leaves. |
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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. |
1.5–12(–20) cm; petiole 1–7(–15) cm, long hairs sparse to abundant, spreading to ± ascending, rarely loosely appressed, 1–2(–2.5) mm, usually stiff, sometimes weak (subsp. chamissonis), verrucose, short and/or crisped hairs absent or sparse to abundant, cottony hairs absent, glands absent or sparse; leaflets separate to ± overlapping, central obovate, 1–3.5(–4.5) × 0.5–2(–3) cm, usually petiolulate, petiolule to 5 mm, base cuneate, margins slightly revolute, distal ± 3/4 incised ± 1/2 to midvein, teeth (2–)3–4(–6) per side, ± approximate to distant, surfaces dissimilar, often strongly so, abaxial white to gray, long hairs 0.5–1.8 mm, cottony-crisped hairs ± dense, adaxial green, sometimes grayish green, long hairs sparse to abundant, short-crisped hairs sparse to abundant. |
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Cauline leaves | 1–2(–3). |
(0–)1–2. |
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Inflorescence(s) | (1–)3–10-flowered, usually openly cymose. |
1–7(–15)-flowered. |
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Pedicels | 1–3(–5) cm, straight to slightly recurved in fruit. |
1.5–5 cm in flower, to 6(–10) cm in fruit. |
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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-lanceolate to lanceolate-elliptic, 2–5(–7) × 0.4–1.2(–1.5) mm, 1/4–1/2 as wide as sepals, margins usually flat, red glands absent or sparse and inconspicuous; hypanthium 3–5 mm diam.; sepals 3–6(–8) mm, apex acute; petals 4–7(–10) × 4–7(–9) mm, ± longer than sepals; filaments 0.8–1 mm, anthers 0.4 mm; carpels 28–40, apical hairs absent, styles conic-columnar, strongly papillate-swollen in proximal 1/5–1/3, 1–1.5 mm. |
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Achenes | 1.5–1.8 mm, smooth to faintly rugose, not carunculate. |
1.1 mm. |
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Potentilla versicolor |
Potentilla arenosa |
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Phenology | Flowering summer. | |||||
Habitat | Rocky, alpine meadows, seasonally moist slopes, near streams or snowmelt | |||||
Elevation | 2100–3200 m (6900–10500 ft) | |||||
Distribution |
NV; OR
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AK; AB; BC; MB; NT; NU; QC; SK; YT; Eurasia |
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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.) |
Subspecies 2 (2 in the flora). The name Potentilla arenosa is now used for most arctic and subarctic plants previously treated as P. hookeriana or P. nivea subsp. hookeriana (Lehmann) Hiitonen. As noted by J. Soják (1986), the type of P. hookeriana has quinate leaves; that name is now restricted to a Rocky Mountain species in sect. Rubricaules. The arctic and subarctic material was briefly (1989–1999) called P. nivea, as discussed under that species. Because the type of P. nivea var. arenosa and other northern Asian specimens correspond closely to the North American plants, the name P. arenosa is assigned here. The two subspecies differ only in one character, the petiole hairs, but are largely allopatric. Subspecies arenosa occurs in western and northern Greenland, northern North America (very northern in the east), and northern Asia (and perhaps northeasternmost European Russia); subsp. chamissonis occurs in southern Greenland, northeastern North America (more southern than subsp. arenosa), and northern Europe at least east to the Urals. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 9, p. 171. | FNA vol. 9, p. 200. | ||||
Parent taxa | Rosaceae > subfam. Rosoideae > tribe Potentilleae > Potentilla > sect. Multijugae | Rosaceae > subfam. Rosoideae > tribe Potentilleae > Potentilla > sect. Niveae | ||||
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Subordinate taxa | ||||||
Synonyms | P. nivea var. arenosa | |||||
Name authority | Rydberg: in N. L. Britton et al., N. Amer. Fl. 22: 344. (1908) | (Turczaninow) Juzepczuk: in V. L. Komarov et al., Fl. URSS 10: 137. (1941) | ||||
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