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common silverweed, Pacific cinquefoil, silver weed cinquefoil, silverweed

fan-foil, fan-leaf cinquefoil, fanleaf or fanfoil or Mount Rainier cinquefoil, fringe-leaf cinquefoil, high mountain cinquefoil

Habit Plants ± openly matted; caudex branches short to elongate, ± stout.
Stems

ascending to erect, (0.3–)1–3 dm, lengths 2 times basal leaves.

Basal leaves

petiole (0.5–)1–15(–25) cm, long hairs absent or sparse to dense, 1.5–3.5 mm;

larger leaflets (0.4–)0.5–5(–7) × (0.2–)0.3–2(–3) cm, surfaces: abaxial with long hairs absent or sparse to abundant, not restricted to veins, 0.5–2(–2.5) mm, cottony-crisped hairs usually dense or usually absent (in subsp. groenlandica), adaxial with long hairs absent or sparse to abundant, cottony-crisped hairs usually absent, sometimes sparse to common (especially subsp. yukonensis).

2-ranked, ternate, (1–)3–12(–20) cm;

stipules: apex rounded;

petiole (0.5–)1–15(–18) cm, hairs and glands usually absent;

leaflets 3, central widely obovate to flabellate, (0.5–)1–5 × (0.4–)1–3(–3.5) cm, petiolule 0–5(–10) mm, margins flat, not or shallowly lobed (sinuses extending less than 1/2 to midvein), distal 1/2–3/4 usually unevenly incised 1/4–1/2 to midvein, teeth 3–7 per side, often secondarily toothed, surfaces similar, green, hairs absent or sparse, rarely common, 0.5–1 mm, glands absent or sparse.

Inflorescences

1–6-flowered.

Pedicels

straight, 0.3–4.5(–5) cm, not much longer in fruit than in flower.

Flowers

epicalyx bractlets narrowly to broadly ovate-triangular or linear to elliptic, (2–)2.5–7(–8) × (0.3–)0.5–3(–3.5) mm, often 2-fid or dentate;

sepals (3–)3.5–7(–9) mm, apex subacute to acuminate;

petals (4–)5–15(–20) × (2.5–)3–10(–12) mm;

filaments (1–)2.5–3.5(–4.5) mm, anthers 0.7–1.3 mm;

carpels (10–)20–200(–250).

epicalyx bractlets often toothed or 2-lobed, elliptic to oval, 3.5–7 × (1–)1.5–3 mm, margins flat;

hypanthium 3–7 mm diam.;

sepals 4–8 mm, apex acute to obtuse;

petals dark yellow, (5–)6–10(–12) × (3–)5–10 mm;

filaments 1.5–3 mm, anthers 0.6–1.5 mm;

carpels 20–50, styles filiform, not or slightly papillate-swollen proximally, 1.6–2.5 mm.

Achenes

2 mm.

1.2–1.5 mm.

2n

= 28.

Potentilla anserina

Potentilla flabellifolia

Phenology Flowering summer.
Habitat Moist to wet or swampy, sometimes dry, stream banks, lakeshores, meadows, in conifer woodlands, subalpine and alpine grassy, rocky slopes, near or above timberline
Elevation 1000–3700 m (3300–12100 ft)
Distribution
from FNA
AK; AZ; CA; CO; CT; IA; ID; IL; IN; MA; ME; MI; MN; MT; ND; NE; NH; NM; NV; NY; OH; OR; RI; SD; UT; VT; WA; WI; WY; AB; BC; MB; NB; NL; NS; NT; NU; ON; PE; QC; SK; YT; Mexico; South America (Argentina, Chile); Eurasia; Pacific Islands (New Guinea, New Zealand); s Australia
[WildflowerSearch map]
[BONAP county map]
from FNA
CA; ID; MT; NV; OR; WA; WY; AB; BC
[WildflowerSearch map]
[BONAP county map]
Discussion

Subspecies 4 or 5 (4 in the flora).

Potentilla anserina is polymorphic in most features, especially in hairiness, but also in size and in degree of dissection of leaflets, epicalyx bractlets, and sepals. While most of the variation described by A. G. Blytt (1906) is taxonomically insignificant, A. Rousi (1965) found support for three northern races: subspp. anserina, egedei, and pacifica. He also suggested that P. yukonensis Hultén might qualify as a separate subspecies. This treatment follows J. Soják (1994) in accepting four northern subspecies of P. anserina, all present in North America.

A. Rousi (1965) demonstrated partial interfertility between the races of Potentilla anserina, which form intermediates in all zones of contact. The distinctness of the four races, in spite of intermediates, is upheld by being partly allopatric and occupying different habitats where they are sympatric. As partly interfertile parapatric entities, they are best treated as subspecies.

The vast majority of chromosome counts are tetraploid. Tetraploid plants (2n = 28) are fully fertile; hexaploids (2n = 42) are largely pollen and seed sterile; pentaploids (2n = 35) are probably occasional hybrids (S. Erlandsson 1942, 1942b; A. Rousi 1965). A. Kurtto et al. (in J. Jalas et al. 1972+, vol. 13) considered numbers above tetraploid level as cases of occasional autopolyploidy.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Potentilla flabellifolia is found in the mountains from southern British Columbia, southwestern Alberta, and southwestern Montana to the southern Sierra Nevada of California.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Key
1. Epicalyx bractlets equal to or longer than sepals, often 2-fid or dentate; leaflet surfaces: abaxial with cottony-crisped hairs dense, long hairs common to abundant, on and between veins, adaxial glabrous or sparsely to densely hairy; achenes with dorsal groove; inland and seashore plants
→ 2
1. Epicalyx bractlets shorter than sepals, usually entire, rarely 2-fid or dentate; leaflet surfaces: abaxial with cottony-crisped hairs absent or sparse to dense, long hairs absent or sparse, on veins, adaxial usually glabrous, rarely sparsely to densely hairy; achenes without dorsal groove; seashore or near-coastal plants
→ 3
2. Hypanthium patelliform (wider than deep) in fruit; epicalyx bractlets narrowly to broadly ovate-triangular, equal to sepals; most of North America.
subsp. anserina
2. Hypanthium turbinate (± as deep as wide) in fruit; epicalyx bractlets usually linear to elliptic, longer than sepals, rarely subequal; interior w Canada and Alaska.
subsp. yukonensis
3. Carpels (20–)50–200(–250); leaves (3–)10–50(–75) cm; leaflets (4–)5–10(–15) per side, abaxial surfaces densely hairy, teeth (4–)6–12(–16) per side, teeth apices acute to acuminate, rarely subacute; flowers 1–2.5(–3.5) cm diam.
subsp. pacifica
3. Carpels 25–60; leaves (1–)2–10 cm, rarely longer; leaflets 2–4(–5) per side, abaxial surfaces glabrous, sometimes sparsely to densely hairy, teeth 2–6(–10) per side, teeth apices rounded to subacute; flowers 0.8–1.5 cm diam.
subsp. groenlandica
Source FNA vol. 9, p. 127. FNA vol. 9, p. 190.
Parent taxa Rosaceae > subfam. Rosoideae > tribe Potentilleae > Potentilla > sect. Pentaphylloides Rosaceae > subfam. Rosoideae > tribe Potentilleae > Potentilla > sect. Aureae
Sibling taxa
P. albiflora, P. ambigens, P. anachoretica, P. angelliae, P. anglica, P. arenosa, P. argentea, P. arizonica, P. basaltica, P. bicrenata, P. biennis, P. biflora, P. bimundorum, P. bipinnatifida, P. brevifolia, P. breweri, P. bruceae, P. brunnescens, P. canadensis, P. concinna, P. cottamii, P. crantzii, P. crebridens, P. crinita, P. cristae, P. demotica, P. drummondii, P. effusa, P. elegans, P. erecta, P. flabellifolia, P. fragiformis, P. furcata, P. glaucophylla, P. gracilis, P. grayi, P. hickmanii, P. hippiana, P. holmgrenii, P. hookeriana, P. hyparctica, P. inclinata, P. intermedia, P. jepsonii, P. johnstonii, P. lasiodonta, P. litoralis, P. macounii, P. millefolia, P. modesta, P. morefieldii, P. multijuga, P. multisecta, P. nana, P. newberryi, P. nivea, P. norvegica, P. ovina, P. paucijuga, P. pedersenii, P. pensylvanica, P. plattensis, P. pseudosericea, P. pulchella, P. pulcherrima, P. recta, P. reptans, P. rhyolitica, P. rimicola, P. rivalis, P. robbinsiana, P. rubella, P. rubricaulis, P. sanguinea, P. saximontana, P. sierrae-blancae, P. simplex, P. sterilis, P. stipularis, P. subgorodkovii, P. subjuga, P. subvahliana, P. subviscosa, P. supina, P. thurberi, P. thuringiaca, P. tikhomirovii, P. townsendii, P. uliginosa, P. uschakovii, P. vahliana, P. verna, P. versicolor, P. villosa, P. villosula, P. vulcanicola, P. wheeleri
P. albiflora, P. ambigens, P. anachoretica, P. angelliae, P. anglica, P. anserina, P. arenosa, P. argentea, P. arizonica, P. basaltica, P. bicrenata, P. biennis, P. biflora, P. bimundorum, P. bipinnatifida, P. brevifolia, P. breweri, P. bruceae, P. brunnescens, P. canadensis, P. concinna, P. cottamii, P. crantzii, P. crebridens, P. crinita, P. cristae, P. demotica, P. drummondii, P. effusa, P. elegans, P. erecta, P. fragiformis, P. furcata, P. glaucophylla, P. gracilis, P. grayi, P. hickmanii, P. hippiana, P. holmgrenii, P. hookeriana, P. hyparctica, P. inclinata, P. intermedia, P. jepsonii, P. johnstonii, P. lasiodonta, P. litoralis, P. macounii, P. millefolia, P. modesta, P. morefieldii, P. multijuga, P. multisecta, P. nana, P. newberryi, P. nivea, P. norvegica, P. ovina, P. paucijuga, P. pedersenii, P. pensylvanica, P. plattensis, P. pseudosericea, P. pulchella, P. pulcherrima, P. recta, P. reptans, P. rhyolitica, P. rimicola, P. rivalis, P. robbinsiana, P. rubella, P. rubricaulis, P. sanguinea, P. saximontana, P. sierrae-blancae, P. simplex, P. sterilis, P. stipularis, P. subgorodkovii, P. subjuga, P. subvahliana, P. subviscosa, P. supina, P. thurberi, P. thuringiaca, P. tikhomirovii, P. townsendii, P. uliginosa, P. uschakovii, P. vahliana, P. verna, P. versicolor, P. villosa, P. villosula, P. vulcanicola, P. wheeleri
Subordinate taxa
P. anserina subsp. anserina, P. anserina subsp. groenlandica, P. anserina subsp. pacifica, P. anserina subsp. yukonensis
Synonyms Argentina anserina
Name authority Linnaeus: Sp. Pl. 1: 495. (1753) Hooker ex Torrey & A. Gray: Fl. N. Amer. 1: 442. (1840)
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