Potentilla bipinnatifida |
Potentilla uliginosa |
|
---|---|---|
bipinnate cinquefoil, potentille bipinnatifide, tansy cinquefoil |
Cunningham Marsh cinquefoil |
|
Habit | Plants rosetted to tufted; taproots not fleshy-thickened. | |
Stems | ascending to erect, (1–)2–5 dm. |
probably prostrate to decumbent, or ± ascending in supporting vegetation, 2.5–5.5 dm, lengths 1–2 times basal leaves. |
Basal leaves | subpinnate to subpalmate, (6–)10–25 cm; petiole (2–)5–15 cm, long hairs dense, appressed, 1–2 mm, soft to ± stiff, short hairs absent, crisped hairs sparse, glands absent, sparse, or obscured; leaflets 2–3 per side, on distal 1/6–1/3(–1/2) of leaf axis, separate to ± overlapping, terminal ones oblanceolate, (2–)3–6(–10) × 1–2(–3.5) cm, margins revolute, incised 3/4+ to midvein, undivided medial blade 1.5–6 mm wide, teeth 5–8 per side, ± linear, surfaces ± to strongly dissimilar, abaxial usually white, rarely grayish, long hairs abundant especially on veins, 1–2 mm, ± weak, short hairs absent or obscured, cottony (and crisped) hairs ± dense, glands absent or obscured, adaxial green to grayish, long hairs sparse to abundant, loosely appressed, 0.5–1.5 mm, short hairs absent or sparse, crisped and/or cottony hairs sparse to common, glands sparse to common. |
pinnate with distal leaflets ± confluent, 15–32 × 2–4 cm; petiole 5–10(–15) cm, straight hairs absent or sparse to common, appressed, 0.5–1.5 mm, stiff, cottony hairs absent, glands absent or sparse; primary lateral leaflets 6–10(–12) per side (irregularly paired), on distal ± 1/2 of leaf axis, loosely overlapping to proximally separate, largest ones cuneate to flabellate, 1.2–2.2 × 1–3 cm, ± whole margin unevenly incised 3/4 to nearly to midvein, ultimate segments (3–)5–10(–15), linear to narrowly oblanceolate, 5–17 × 1–2.5 mm, apical tufts less than 0.5 mm, surfaces green, not glaucous, straight hairs sparse (often glabrate adaxially), appressed, 0.5–1(–1.5) mm, stiff, cottony hairs absent, glands absent or sparse. |
Cauline leaves | 2–4. |
2. |
Inflorescences | (4–)10–50(–100)-flowered, congested or elongating in fruit. |
6–10-flowered, very openly cymose. |
Pedicels | 0.2–0.8 cm (proximal to 2 cm). |
1–6 cm, ± recurved in fruit. |
Flowers | epicalyx bractlets narrowly elliptic to lanceolate, 2.5–6 mm, lengths ± 2/3 times sepals, margins flat; hypanthium 3–5 mm diam.; sepals 3–6 mm, apex ± acute, abaxial surfaces: venation indistinct, glands absent, sparse, or obscured; petals yellow, 3–5 × 3–4 mm, lengths ± equal to sepals; filaments 0.5–2 mm, anthers 0.3–0.5 mm; carpels 50–80, styles papillate-swollen in proximal 1/2–3/4+, 1–1.2 mm. |
epicalyx bractlets narrowly elliptic to oblong-ovate, 4–6 × 1–2.5 mm; hypanthium 5–6 mm diam.; sepals 4–7 mm, apex acute; petals 6–10 × 5–8 mm; filaments (1.5–)2–3 mm, anthers 0.7–1.2 mm; carpels ca. 10, styles 2.5–3.5 mm. |
Achenes | 1–1.2 mm, smooth to faintly rugose. |
2–2.6 mm, smooth, ± carunculate. |
2n | = 56. |
|
Potentilla bipinnatifida |
Potentilla uliginosa |
|
Phenology | Flowering summer. | Flowering spring–summer. |
Habitat | Open shortgrass prairie, alkaline bottoms, streamsides in sagebrush, disturbed sites | Permanent oligotrophic wetlands |
Elevation | 10–3400 m (0–11200 ft) | 30–40 m (100–100 ft) |
Distribution |
AK; CO; ID; MI; MN; MT; ND; NE; NM; SD; UT; WY; AB; MB; NT; ON; QC; SK; YT
|
CA |
Discussion | Potentilla bipinnatifida is similar to P. litoralis in habit and leaf dissection but has flat, silky epicalyx bractlets and sepals with no evident glands. Vestiture is generally silkier, and the silvery to bicolor leaves are white-cottony abaxially. The two species are sympatric in the plains of Canada, with some intergradation; P. bipinnatifida is also common south to Colorado, where it is found in intermontane meadows and sagebrush flats. Outlying populations occur in Blaine and Custer counties, Idaho, and Duchesne and Piute counties, Utah. Eastern collections from disturbed sites might be adventive. Potentilla missourica Hornemann ex Lindley and P. normalis Besser ex Sprengel are older names for this species; both were rejected against a conserved P. bipinnatifida with designated lectotypes (see J. Soják 2008b). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Of conservation concern. Potentilla uliginosa is known only from a handful of historical collections from Cunningham Marsh, one of three wetlands in southern Sonoma County that harbor a suite of disjunct and regionally rare species (B. C. Johnston and B. Ertter 2010). Although previously included in P. hickmanii, P. uliginosa differs in having woodier caudices, longer stems and leaves, and more deeply incised leaflets occupying less of the leaf axis. Potentilla uliginosa is presumed extinct; however, a morphologically comparable collection of the P. millefolia complex from Josephine County, Oregon (Deer Creek, near Selma, 14 June 1929, Applegate 5735, UC), opens the possibility of additional undiscovered populations in the mountains of northwestern California. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 9, p. 217. | FNA vol. 9, p. 175. |
Parent taxa | Rosaceae > subfam. Rosoideae > tribe Potentilleae > Potentilla > sect. Pensylvanicae | Rosaceae > subfam. Rosoideae > tribe Potentilleae > Potentilla > sect. Multijugae |
Sibling taxa | ||
Synonyms | P. pensylvanica var. bipinnatifida | |
Name authority | Douglas: in W. J. Hooker, Fl. Bor.-Amer. 1: 188. (1832) | B. C. Johnston & Ertter: J. Bot. Res. Inst. Texas 4: 14, fig. 1. (2010) |
Web links |