Potentilla millefolia
Potentilla pedersenii
cut-leaf cinquefoil, feather cinquefoil, feather or many-leaf or Klamath cinquefoil, many leaf cinquefoil
not sheathed with marcescent whole leaves.
usually prostrate, sometimes ± decumbent, 0.4–2(–3) dm, lengths 1–2 times basal leaves.
ascending to nearly erect, 0.4–2 dm.
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.
often both ternate and palmate or subpalmate on same plant, 2.5–4 cm;
petiole 1.5–2.5 cm, long hairs common to abundant, loosely appressed to ascending-spreading, 1–2 mm, weak to ± stiff, verrucose, crisped(/short) hairs absent or sparse to common, cottony hairs absent, glands sparse to common;
leaflets 3–5, proximalmost separated by 0–2 mm, central broadly elliptic to obovate, 1–1.5 × 0.5–0.9 cm, petiolules 1–2 mm, distal 2/3–3/4 of margin incised 1/2–3/4 to midvein, teeth (2–)3–4 per side, 4–6 mm, apical tufts ± 1 mm, abaxial surfaces grayish white to white, long hairs abundant (sometimes obscuring entire surface), cottony-crisped hairs abundant to dense, short hairs absent or obscured, glands sparse to common but usually obscured, adaxial grayish green to gray, long hairs sparse to abundant, 1–1.5(–2) mm, ± weak, short (short-crisped) hairs absent or sparse, rarely common, cottony hairs absent, glands absent or sparse, rarely common.
(0–)1–2.
0–2.
3–6(–10)-flowered, loosely cymose, sometimes racemiform.
(1–)3–7-flowered, open, branch angle 30–50°.
(0.5–)1–2(–4.5) cm, ± recurved in fruit.
1–2 cm, proximal to 4 cm.
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 narrowly ovate to elliptic, 4–5 × 1–1.4 mm;
hypanthium 3–4 mm diam.;
sepals 4–6 mm, apex subacute to acute, glands sparse to common, usually not obscured;
petals pale yellow, usually not overlapping, 6–7 × 4–8 mm, distinctly longer than sepals;
filaments 1–2 mm, anthers ± 0.4 mm;
carpels 40–80, styles 0.8–0.9 mm.
1.5–2 mm, smooth, often ± carunculate.
1.1–1.2 mm.
Potentilla millefolia
Potentilla pedersenii
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.)
Potentilla pedersenii and P. uschakovii account for the majority of arctic populations previously included in a broadly defined P. rubricaulis. The diagnostic morphological characters between the two species can be variable and overlapping; they are treated separately in part because of differences in presumed parental combinations. Whereas P. pulchella is the probable sect. Pensylvanicae parent for both species, the putative sect. Niveae parent for P. pedersenii is P. arenosa subsp. arenosa; that of P. uschakovii is P. subvahliana. Reflecting this parentage, P. pedersenii is distinguished by caudex branches with no marcescent whole leaves, verrucose long hairs on petioles, and inflorescences with usually several relatively small flowers. In contrast, P. uschakovii often has marcescent whole leaves sheathing the caudex branches, smooth long hairs on petioles, and one- or few-flowered inflorescences with mostly larger flowers. These generalities aside, there is much variation within both species, such that each island or population group may have its own features; it is probable that both P. pedersenii and P. uschakovii have evolved from multiple hybridization events.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
CA
OR
Flora NW
PNW Herbaria
WildflowerSearch
iNaturalist
USDA Plants Database
