Potentilla millefolia
Potentilla vahliana
cut-leaf cinquefoil, feather cinquefoil, feather or many-leaf or Klamath cinquefoil, many leaf cinquefoil
potentille de Vahl, Vahl's cinquefoil
usually stout, columnar, sheathed with marcescent whole leaves.
usually prostrate, sometimes ± decumbent, 0.4–2(–3) dm, lengths 1–2 times basal leaves.
erect, (0.2–)0.3–0.8(–1) dm, lengths 2–4(–5) times basal leaves.
pinnate with distal leaflets ± confluent, 2–15(–20) × 1–3 cm;
petiole 0.5–2(–3) cm, straight hairs sparse to abundant, appressed to spreading, 0.5–1.5 mm, stiff, cottony hairs absent, glands absent or sparse;
primary lateral leaflets (3–)5–13 per side, on distal 2/3–3/4+ of leaf axis, separate to overlapping, largest ones cuneate to flabellate, 0.5–1.5(–2) × 0.5–2 cm, distal 2/3 to whole margin palmately or unevenly, rarely pinnately, incised 2/3 to completely to midvein, ultimate teeth or segments (1–)2–10, linear to broadly oblanceolate, 2–10 × (0.5–)1–2 mm, apical tufts to 1 mm, surfaces green to grayish green, not glaucous, straight hairs sparse to abundant, appressed to spreading, 0.5–1.5(–2) mm, stiff, cottony hairs absent, glands sparse to common.
1–3 cm;
petiole 0.5–2 cm, long hairs common to abundant, ascending to spreading, 0.5–1.5(–2) mm, soft to weak, smooth, short hairs absent, crisped/short-cottony hairs sparse to abundant, glands sparse to common;
leaflets separate to slightly overlapping, central obovate, 0.8–1.2(–1.5) × 0.5–1(–1.5) cm, sessile or subsessile, base cuneate, margins revolute, distal ± 1/2 incised (1/3–)1/2–3/4 to midvein, teeth 2–3 per side, ± approximate to distant, surfaces ± dissimilar, abaxial yellowish white or grayish, long hairs 1–2 mm, cottony-crisped hairs ± dense, adaxial green to yellowish gray, long(/short) hairs common to abundant, crisped hairs absent or sparse.
(0–)1–2.
0–1(–2).
3–6(–10)-flowered, loosely cymose, sometimes racemiform.
1–2(–3)-flowered.
(0.5–)1–2(–4.5) cm, ± recurved in fruit.
0.5–1.5 cm in flower, to 3.5 cm in fruit.
epicalyx bractlets ± elliptic, 2–4(–6) × 1–2(–2.5) mm;
hypanthium 3–6 mm diam.;
sepals 4–6(–8) mm, apex acute;
petals 4–8(–10) × 3–7(–9) mm;
filaments 2–3.5 mm, anthers 0.7–1 mm;
carpels 10–30, styles (1.5–)2–3 mm.
epicalyx bractlets broadly ovate, 2.5–4(–5) × 1.5–3 mm, ± as wide as sepals, margins flat or revolute, red glands absent;
hypanthium 2–4 mm diam.;
sepals 2.5–5(–6) mm, apex subacute to acute;
petals 8–10 × 7–12 mm, significantly longer than sepals;
filaments 1–1.2 mm, anthers 0.4–0.6 mm;
carpels 30–40, apical hairs absent, styles narrowly columnar, distinctly papillate-swollen at very base, 1–1.1 mm.
1.5–2 mm, smooth, often ± carunculate.
1.1–1.5 mm.
= 42, 49, 56.
Potentilla millefolia
Potentilla vahliana
Potentilla millefolia occurs from central Oregon to the east side of the Sierra Nevada of California, with a disjunct occurrence on the alkaline flats of Reese River Valley, Nevada. Significant variation occurs in vestiture type, leaflet dissection, and flower size, but with minimal geographic correlation. The most distinctive variant, represented by the type of P. klamathensis, has relatively long, slender, spreading, pustule-based hairs, often intermixed with shorter hairs. This vestiture type does not appear to be correlated with any other characters or geographic distribution and may vary within a population.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
As circumscribed here, Potentilla vahliana is confined to northeastern arctic Canada (including northernmost Quebec) and western Greenland. Plants previously assigned to P. vahliana from northwestern Greenland, Yukon, most of arctic Canada, and Alaska are now relegated to P. subvahliana.
Plants from western Greenland, whence Potentilla vahliana was described and typified, have petioles with at least some short cottony or crisped hairs in addition to long, smooth hairs, and the styles have distinct papillae at the very base. These features are derived from a combination of the P. uniflora Ledebour and P. nivea groups. Potentilla vahliana is of a higher polyploidy than the species of the P. uniflora group. Potentilla vahliana is treated here as a geographically restricted species, most probably from cross(es) between P. nivea in the narrow sense (probably the Atlantic race, often 2n = 70) and P. subvahliana (2n = 28); it shares several features with the latter, not least of which is leaf dissection and the columnar structure of the caudex.
In mainland Quebec, plants combine features from Potentilla arenosa and P. vahliana; that is, the straight hairs are slightly verrucose, not smooth as in P. nivea, P. subvahliana, and P. vahliana in the narrow sense. They form populations and probably should be described as a new hybrid species.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
CA
OR
Flora NW
PNW Herbaria
WildflowerSearch
iNaturalist
USDA Plants Database
