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Alaska cinquefoil, finely villous cinquefoil

erect cinquefoil, tormentil

Habit Plants densely tufted.
Caudex branches

stout, sometimes ± columnar, not sheathed with marcescent whole leaves.

Stems

ascending to erect, 0.2–1.5(–2) dm, lengths 1.5–3(–4) times basal leaves.

mostly ascending to erect, not flagelliform, openly branched, not rooting at nodes, (0.5–)1–5(–7) dm.

Basal leaves

1–5.5(–7) cm;

petiole 0.5–3.5(–5) cm, long hairs common to dense, ascending to spreading, loosely appressed, sometimes retrorse, 1–2(–3) mm, soft, smooth, crisped/short-cottony hairs usually sparse, sometimes common, glands absent or sparse to common or obscured;

leaflets overlapping, central broadly obovate to obtriangular, 0.8–2.5 × 0.6–2 cm, sessile to subsessile, base broadly cuneate, margins revolute, distal 1/2–2/3(–3/4) incised ± 1/2 to midvein, teeth 2–3(–4) per side, ± approximate to ± distant, surfaces ± dissimilar, abaxial grayish to white or yellowish white, long hairs 1.5–2.5 mm, cottony-crisped hairs ± dense, adaxial grayish green, long hairs abundant to dense, crisped hairs absent, sparse, or obscured.

ephemeral, usually ternate, 2–15 cm;

petiole (1–)3–13 cm, long hairs sparse to common, appressed, 0.5–1 mm, stiff, glands absent;

leaflets 3(–5), central ± obovate to cuneate, (0.5–)1–2 × (0.3–)1–1.5 cm, distal 1/2–2/3 of margin incised ± 1/3 to midvein, teeth 2–4 per side, surfaces similar, green (abaxial sometimes paler), glabrate or sparsely to moderately hairy.

Cauline leaves

(0–)1–2(–3).

(0–)1–3(–7) proximal to 1st flowering node, expanded at anthesis, usually ternate, rarely palmate (or appearing so because of leafletlike stipules), (0.5–)1–3 cm;

petiole usually 0 cm;

leaflets 3(–5), usually much narrower than those of basal leaves, narrowly cuneate to oblanceolate, (0.5–)1–3 × (0.2–)0.5–1 cm, distal 1/3–2/3 of margin incised ± 1/2 to midvein, teeth 2–4(–6) per side, apex usually obtuse to acute.

Inflorescences

(1–)2–3(–4)-flowered.

3–30-flowered, cymose, open.

Pedicels

0.5–3(–5) cm in flower, to 4(–6) cm in fruit.

(1–)2–3(–5) cm.

Flowers

epicalyx bractlets broadly lanceolate to narrowly ovate, 3–7(–8) × 1.5–3(–3.5) mm, 2/3 to as wide as sepals, margins ± revolute, red glands absent;

hypanthium (3–)4–6 mm diam.;

sepals 4–7(–8) mm, apex acute or rarely acuminate;

petals 5–10 × 6–12 mm, significantly longer than sepals;

filaments 1.1–1.4 mm, anthers 0.5–0.8 mm;

carpels 40–70, apical hairs absent or sparse (straight), styles narrowly columnar to conic-tapered, papillate-swollen in proximal 1/5 or less, 1–1.2 mm.

4(–5)-merous;

epicalyx bractlets ovate to narrowly elliptic, 1.5–4 × 0.5–1 mm, much smaller than to sometimes equal to sepals;

hypanthium 1.5–2.5 mm diam.;

sepals (2–)3–5 mm, apex broadly acute;

petals (2–)4–6 × (1.5–)3–6 mm, apex ± retuse;

stamens 15–20, filaments 2–3.8 mm, anthers 0.4–0.6 mm;

carpels 4–8(–20), styles 0.9–1.4 mm.

Achenes

0.9–2 mm.

1.2–2 mm, rugose.

Rootstocks

erect to horizontal, irregularly thickened, 1–8 cm.

2n

= 28 (Russian Far East).

= 28 (Eurasia).

Potentilla villosula

Potentilla erecta

Phenology Flowering late spring to summer. Flowering unknown.
Habitat Rocky alpine heaths, outcrops, scree and talus, gravel outwash plains, dry tundra, coastal bluffs, stabilized sand dunes, mostly on acidic bedrock Moist, mossy flats and slopes, acidic soil
Elevation 0–2900 m (0–9500 ft) 0–100 m (0–300 ft)
Distribution
from FNA
AK; AB; BC; YT; e Asia (Russian Far East)
[BONAP county map]
from FNA
MA; NS; Europe; w Asia; n Africa; Atlantic Islands (Azores) [Introduced in North America]
[BONAP county map]
Discussion

Potentilla villosula was included previously in P. villosa; the two overlap in the southern and western Alaskan coasts, where a transition is suspected to be associated with differing ploidy levels. The plants from this area with silky hairs and multiflowered inflorescences are assigned to P. villosa; P. villosula has thicker, stiffer, and less silky hairs, fewer teeth per leaflet, narrower bracts, fewer and smaller flowers with narrower epicalyx bractlets and sepals, and fewer achenes (sometimes with single apical hairs). While P. villosa is restricted to relatively rocky sites near the coast from western Alaska to Oregon, P. villosula often occurs on coastal sand dunes, farther inland, and/or farther to the north.

As circumscribed, Potentilla villosula is a major plant of Alaska, especially of the Bering Sea region. The species extends from Alaska and the Yukon to at least central British Columbia. Most of the range given by E. Hultén (1968) for P. villosa belongs to P. villosula. W. J. Cody (1996) accepted the name P. villosula for a common south-central Yukon plant, but the majority of the plants mapped by Cody probably belong to P. subgorodkovii (although the distinction between the two species needs more resolution). Provisionally included here are plants from southern and central Yukon south through the Canadian Rockies, possibly including the type of P. nivea subsp. fallax A. E. Porsild. Such plants tend to be significantly smaller overall than Alaskan P. villosula; at least some have straight hairs on carpel apices.

J. Soják (2004) believed that Potentilla villosula evolved from crosses between P. villosa and P. vulcanicola. The affinity with P. villosa is seen in the sericeous vestiture, number of leaflet teeth, and flower number and size, and with P. vulcanicola in the frequent occurrence of straight hairs on carpel apices in both species. Plants with columnar caudex branches, representing a significant part of the Alaskan material, have been called subsp. congesta. This morphology results from the persistence of marcescent whole leaves for several years (in typical P. villosula only sheaths and petioles are retained). This character suggests that P. subvahliana, with which the form called subsp. congesta is sympatric, may be part of its parentage. Potentilla villosula is accepted here in a fairly collective sense, possibly including several hybrid lineages, but with P. villosa a part of them all.

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

Although included here, Potentilla erecta is questionably extant as a naturalized species in North America and is not currently known from Newfoundland where historically reported. It is a medicinal plant called tormentil, high in tannins and strongly astringent. A tea made from the tuberous rootstock is widely used in Europe and parts of Asia for diarrhea, dysentery, sore throats, and related problems. A decoction is a mild antibiotic used for cuts and minor infections, especially as an anti-inflammatory for gingivitis and other gum problems. The rootstock is used as a red dye.

Another synonym with a long history of use is Potentilla tormentilla Necker, illegitimate by virtue of being superfluous.

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

Source FNA vol. 9, p. 202. FNA vol. 9, p. 136.
Parent taxa Rosaceae > subfam. Rosoideae > tribe Potentilleae > Potentilla > sect. Niveae Rosaceae > subfam. Rosoideae > tribe Potentilleae > Potentilla > sect. Potentilla
Sibling taxa
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. 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. 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. 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
Synonyms P. villosula subsp. congesta Tormentilla erecta
Name authority Jurtzev: in A. I. Tolmatchew, Fl. Arct. URSS 9(1): 319. (1984) (Linnaeus) Raeuschel: Nomencl. Bot, 152. (1797)
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