Potentilla canadensis |
Potentilla bicrenata |
|
---|---|---|
dwarf cinquefoil |
||
Stems | initially ascending to erect, soon becoming prostrate, flagelliform, not branched, eventually rooting at some nodes, (0.3–)0.5–12 dm. |
0.2–0.8(–1.5) dm, lengths 1/2–1 1/2 times basal leaves. |
Basal leaves | ± persistent, usually palmate, 2–9(–11) cm; petiole 1–7(–8) cm, long hairs abundant to dense, appressed to spreading, 1.5–3 mm, mostly ± weak, glands absent or sparse; leaflets (3–)5(–7), central mostly ± obovate to cuneate, sometimes narrowly so, (0.5–)1–4(–6) × (0.5–)0.8–2(–3) cm, distal 1/2 of margin incised 1/4–1/3 to midvein, teeth 2–7 per side, surfaces similar to ± dissimilar, abaxial green to silvery white, sparsely to densely hairy, adaxial green, sparsely to moderately hairy. |
palmate, (2–)4–10(–15) cm; petiole (1–)2–6(–10) cm, straight hairs abundant, ± appressed to ascending, 1.5–2 mm, stiff, cottony hairs usually absent, glands sparse, often obscured; leaflets 5–7(–9), on tip or at least less than distal 1/10 of leaf axis, slightly overlapping, proximal pair separated from others by 0(–1) mm of leaf axis, central leaflets ± oblanceolate, 1–4(–5.5) × 0.5–1 cm, petiolules 0(–3) mm, less than distal 1/5(–1/3) of margins incised ± 1/2 to midvein, teeth 0–1(–3) per side, separate, 0.5–2 mm, surfaces strongly to ± dissimilar, abaxial grayish white to white, straight hairs abundant, ± appressed, 1–1.5(–2) mm, weak to stiff (especially on veins), cottony hairs common to dense, glands absent or obscured, adaxial green to grayish green, straight hairs ± abundant, appressed, 0.5–1 mm, stiff, cottony hairs absent, rarely sparse, glands absent or obscured. |
Cauline leaves | 0–1 proximal to 1st flowering node, not fully expanded at anthesis, usually palmate, 2–7(–9) cm; petiole (0.5–)1–6(–7.5) cm; leaflets (3–)5, ± resembling those of basal leaves, apex rounded to obtuse. |
|
Inflorescences | solitary flowers at stolon nodes. |
2–5(–8)-flowered. |
Pedicels | (1–)2–5(–9) cm. |
1–3(–4.5) cm. |
Flowers | 5-merous; epicalyx bractlets linear to lanceolate-elliptic, (2–)3–5(–6) × 0.8–1.5 mm, slightly smaller than to ± equal to sepals; hypanthium 2.5–5 mm diam.; sepals (2–)3–5(–6) mm, apex acute; petals 4–6(–8) × 3.5–6.5(–8) mm, apex rounded to slightly retuse; stamens ca. 20, filaments 0.5–2 mm, anthers 0.4–1 mm; carpels 20–40, styles 0.8–1.4 mm. |
epicalyx bractlets ± lanceolate, 2–4 × 1 mm; hypanthium 3–4 mm diam.; sepals (2.5–)3–5.5 mm, apex ± acute; petals 3.5–7 × 2.5–5.5 mm; filaments 1–2 mm, anthers 0.5–1 mm; carpels 10–20, styles 2 mm. |
Achenes | 1.2–1.4 mm, smooth. |
2 mm, smooth to rugose. |
Rootstocks | erect, stout, 0.5–2 cm. |
|
2n | = 28. |
|
Potentilla canadensis |
Potentilla bicrenata |
|
Phenology | Flowering late Mar–early Jun. | Flowering early summer. |
Habitat | Dry flats and slopes in lawns, pastures, roadsides, cherty slopes, dry meadows, edges of oak and conifer woodlands, often on acidic soil | Outcrops, dry flats, pine duff, in pine and/or juniper woodlands, sagebrush scrub |
Elevation | 0–1500 m (0–4900 ft) | 1900–3300 m (6200–10800 ft) |
Distribution |
CT; DC; DE; KY; MA; MD; ME; MO; NC; NH; NJ; NY; OH; PA; RI; SC; TN; VA; VT; WV; NS; ON
|
AZ; CO; NM; UT; WY
|
Discussion | A cream-colored form (ochroleuca) was described from a now-obliterated site in Massachusetts (M. L. Fernald 1931). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
The entire to tridentate leaflets of Potentilla bicrenata generally serve to distinguish this species from P. concinna. Unequivocal P. bicrenata is most common in Utah and the southern Rocky Mountains from New Mexico to central Colorado; in Arizona, it is documented only from the Kaibab Plateau. Wyoming populations tend to be transitional to P. concinna var. concinna in leaflet toothing and/or petal size. Some collections from as far north as Waterton Lakes National Park, Alberta, vary in the direction of P. bicrenata but are retained here in P. concinna. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 9, p. 134. | FNA vol. 9, p. 179. |
Parent taxa | Rosaceae > subfam. Rosoideae > tribe Potentilleae > Potentilla > sect. Potentilla | Rosaceae > subfam. Rosoideae > tribe Potentilleae > Potentilla > sect. Concinnae |
Sibling taxa | ||
Synonyms | P. canadensis var. pumila, P. canadensis var. villosissima, P. caroliniana, P. pumila | P. concinna var. bicrenata |
Name authority | Linnaeus: Sp. Pl. 1: 498. (1753) | Rydberg: Bull. Torrey Bot. Club 23: 431. (1896) |
Web links |