Potentilla pensylvanica

Linnaeus

Mant. Pl. 1: 76. 1767.

Common names: Prairie cinquefoil potentille de Pennsylvanie
Illustrated
Synonyms: Potentilla atrovirens Rydberg P. brooksensis Jurtzev P. pensylvanica var. arida B. Boivin P. pensylvanica var. brevipila Soják P. sibirica
Treatment appears in FNA Volume 9. Treatment on page 214. Mentioned on page 162, 212, 213, 215, 216.

Stems ascending to erect, (0.3–) 1–4 (–6) dm. Basal leaves pinnate, (2–) 4–20 (–25) cm; petiole 1–8 cm, long hairs sparse to abundant, rarely absent, spreading to ascending, 0.5–3 mm, weak to ± stiff, short hairs abundant to dense, rarely absent, cottony or crisped hairs absent, glands sparse to abundant, often obscured; leaflets (2–) 3–5 (–7) per side, on distal 1/2–3/5 of leaf axis, separate to scarcely overlapping, terminal ones narrowly to broadly oblanceolate, (1–) 1.5–5 (–6) × 0.5–1.5 (–2) cm, margins strongly revolute, incised ± 3/4 to midvein, sometimes more or only ± 1/2, undivided medial blade 2–4 (–8) mm wide, teeth 4–8 (–10) per side, triangular-ovate to linear-elliptic, surfaces usually ± dissimilar, abaxial ± grayish to nearly white, rarely green, long hairs sparse to abundant (mostly on veins), rarely absent, 0.5–1.5 mm, ± weak, short hairs usually abundant to dense, rarely absent, crisped and cottony hairs absent, glands ± abundant, sometimes obscured, adaxial green to gray-green, long hairs sparse to abundant, rarely absent, spreading to ascending, ± 1 mm, short hairs ± abundant, sometimes obscured, rarely absent, cottony and crisped hairs absent, glands ± abundant. Cauline leaves 1–4. Inflorescences (1–) 3–40-flowered, congested or elongating in fruit. Pedicels 0.2–1 cm (proximal to 3.5 cm). Flowers: epicalyx bractlets usually ± lanceolate-elliptic, rarely ± ovate-elliptic, 3–6 (–8) × (1–) 1.5–2 (–2.5) mm, lengths ± equal to sepals, margins ± revolute; hypanthium 3–6 mm diam.; sepals (3–) 4–6 (–8) mm, apex acute to obtuse, abaxial surfaces: venation indistinct, glands abundant, ± evident; petals pale to bright-yellow, (3–) 4–7 × (3–) 4–7 mm, lengths ± equal to sepals; filaments (0.5–) 1–2 mm, anthers 0.5–0.8 (–1) mm; carpels 50–100, styles papillate-swollen in proximal ± 1/2, ± 1 mm. Achenes 1.2 mm, ± to strongly rugose. 2n = 28.


Phenology: Flowering summer.
Habitat: Open prairies, steppe bluffs, shallow gravelly soil, rocky ridges and outcrops, dry stream channels, similar disturbed sites
Elevation: 100–4000 m

Distribution

V9 321-distribution-map.jpg

Alta., B.C., Man., N.W.T., Ont., Que., Sask., Yukon, Alaska, Ariz., Calif., Colo., Idaho, Iowa, Minn., Mont., Nebr., Nev., N.Mex., N.Dak., S.Dak., Tex., Utah, Wyo., Mexico (Tamaulipas), Eurasia

Discussion

Even in the reduced circumscription used here, Potentilla pensylvanica is exceptionally widespread, occurring in North America from Alaska to Hudson Bay, in the Great Plains and the North American Cordillera to northern Mexico. The species also grows across Siberia (where it has sometimes been called P. sibirica) and as isolated occurrences in the southwestern Alps and Spain (J. Soják 1987c; A. Kurtto et al. in J. Jalas et al. 1972+, vol. 13). One place P. pensylvanica does not occur is in Pennsylvania; the epithet was applied by Linnaeus to cultivated plants originating from Canada. Collections from Quebec are probably introductions (J. Cayouette, pers. comm.). The Oregon citation of P. pensylvanica (D. Mansfield 2000) refers to P. jepsonii.

Significant variation occurs within Potentilla pensylvanica, especially regarding vestiture and plant stature. J. Soják (1987c) has described several varieties, all Eurasian except var. brevipila (long hairs 0.6–1 mm); diminutive specimens from the Brooks Range of northern Alaska, isolated from other known populations of P. pensylvanica, have been described as P. brooksensis. Although much of the ecogeographic variation may merit recognition, at least at varietal level, doing so is postponed pending further analysis and clarification of nomenclature. Among the extremes are plants from the Great Plains, which have abundant long silky hairs overlying and obscuring the velvety layer of short hairs (resembling sympatric P. litoralis), and glabrate (except for glands) populations in Alaska. E. Hultén (1968) erroneously referred to the latter as P. pensylvanica var. glabrata (Lehmann) S. Watson; that name is a synonym of P. ovina var. ovina (sect. Multijugae). Most populations in Alaska also have larger than average flowers (petals to 7 × 7 mm, anthers ca. 1 mm).

Although Potentilla pensylvanica var. strigosa Pursh has been one of the most commonly used varieties in North America, the name has been effectively lectotypified by J. Soják (1987c) on a collection from Siberia. Soják identified this collection as the hybrid between P. pensylvanica and the Asian P. sanguisorba D. F. K. Schlechtendal; var. strigosa accordingly does not occur in North America.

Selected References

None.

Lower Taxa

None.

"dm" is not declared as a valid unit of measurement for this property.

... more about "Potentilla pensylvanica"
green +, less grayish +  and nearly white +
green +  and gray-green +
0.08 cm0.8 mm <br />8.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.08 cm0.8 mm <br />8.0e-4 m <br />) +
Barbara Ertter +  and Reidar Elven +
Linnaeus +
compound +  and simple +
opposite +  and alternate +
20 cm200 mm <br />0.2 m <br /> (25 cm250 mm <br />0.25 m <br />) +
4 cm40 mm <br />0.04 m <br /> (20 cm200 mm <br />0.2 m <br />) +
25 cm250 mm <br />0.25 m <br /> (30 cm300 mm <br />0.3 m <br />) +
less cordate or reniform +  and narrowly elliptic +
0.5 cm5 mm <br />0.005 m <br /> (25 cm250 mm <br />0.25 m <br />) +
reduced +
free +  and distinct +
hairy +  and glabrous +
Prairie cinquefoil +  and potentille de Pennsylvanie +
Alta. +, B.C. +, Man. +, N.W.T. +, Ont. +, Que. +, Sask. +, Yukon +, Alaska +, Ariz. +, Calif. +, Colo. +, Idaho +, Iowa +, Minn. +, Mont. +, Nebr. +, Nev. +, N.Mex. +, N.Dak. +, S.Dak. +, Tex. +, Utah +, Wyo. +, Mexico (Tamaulipas) +  and Eurasia +
not +  and aggregated +
100–4000 m +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
0.1 cm1 mm <br />0.001 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
0.8 cm8 mm <br />0.008 m <br /> (2 cm20 mm <br />0.02 m <br />) +
unisexual +  and bisexual +
not +  and aggregated +
deciduous +
on style scar +, hairy +  and glabrous +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.26 cm2.6 mm <br />0.0026 m <br />) +
evident +  and obscured +
crisped +
Open prairies, steppe bluffs, shallow gravelly soil, rocky ridges and outcrops, dry stream channels, similar disturbed sites +
stoloniferous +  and short-rhizomatous +
straight +
weak +  and more or less stiff +
spreading +  and ascending +
abundant +  and sparse +
crisped +
1 cm10 mm <br />0.01 m <br /> (0.05 cm0.5 mm <br />5.0e-4 m <br />) +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
0.7 cm7 mm <br />0.007 m <br /> (1 cm10 mm <br />0.01 m <br />) +
0.3 cm3 mm <br />0.003 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
0.2 cm2 mm <br />0.002 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
(1-)3-40-flowered +
crassinucellate +
bipinnate +, odd-pinnate +, subpalmate +, palmate +  and ternate +
opposite +  and alternate +
marcescent +
well-developed +
persistent +
cauline +  and basal +
reduced +
separate +  and scarcely overlapping +
5 cm50 mm <br />0.05 m <br /> (6 cm60 mm <br />0.06 m <br />) +
1.5 cm15 mm <br />0.015 m <br /> (2 cm20 mm <br />0.02 m <br />) +
1.5 cm15 mm <br />0.015 m <br /> (5 cm50 mm <br />0.05 m <br />) +
oblanceolate +
0.5 cm5 mm <br />0.005 m <br /> (?) +  and 1.5 cm15 mm <br />0.015 m <br /> (?) +
linear +  and oblanceolate +
palmate +  and pinnate +
0.2 cm2 mm <br />0.002 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
inferior +  and superior +
clustered +, biseriate +  and superposed +
3 cm30 mm <br />0.03 m <br /> (5 cm50 mm <br />0.05 m <br />) +
0.2 cm2 mm <br />0.002 m <br /> (1 cm10 mm <br />0.01 m <br />) +
0.5 cm5 mm <br />0.005 m <br /> (1.05 cm10.5 mm <br />0.0105 m <br />) +
free +  and distinct +
0.4 cm4 mm <br />0.004 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
0.3 cm3 mm <br />0.003 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
1 cm10 mm <br />0.01 m <br /> (8 cm80 mm <br />0.08 m <br />) +
Flowering summer. +
adnate +, free +, connate +  and distinct +
pinnate +  and subpinnate or subpalmate +
25 cm250 mm <br />0.25 m <br /> (30 cm300 mm <br />0.3 m <br />) +
1.5 cm15 mm <br />0.015 m <br /> (25 cm250 mm <br />0.25 m <br />) +
often significantly longer +
not arillate +
0.6 cm6 mm <br />0.006 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
persistent +
free +  and distinct +
erect +  and spreading +
lanceolate +  and broadly ovate or deltate +
0.4 cm4 mm <br />0.004 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
Illustrated +
free +  and distinct +
not rooting +
reddish +  and green +
(1-)1.5-3(-4) times basal leaves +
ascending +  and erect +
1 +  and many +
not flagelliform +
palmate +  and pinnate +
0.12 cm1.2 mm <br />0.0012 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
deciduous +
distinct +
subapical +
papillate-swollen +
rough-thickened +
1 cm10 mm <br />0.01 m <br /> (?) +
Potentilla atrovirens +, P. brooksensis +, P. pensylvanica var. arida +, P. pensylvanica var. brevipila +  and P. sibirica +
not fleshy-thickened +
Potentilla pensylvanica +
Potentilla sect. Pensylvanicae +
species +
4 +  and 8 +
triangular-ovate +  and linear-elliptic +
inconspicuous +
enlarged +
biennial +, annual +  and perennial +
herb +  and matted +