Potentilla anserina subsp. pacifica

(Howell) Rousi

Ann. Bot. Fenn. 2: 104. 1965.

Common names: Pacific silverweed
EndemicIllustrated
Basionym: Potentilla pacifica Howell Fl. N.W. Amer., 179. 1898
Synonyms: Argentina occidentalis Rydberg A. pacifica (Howell) Rydberg P. anserina var. grandis Torrey & A. Gray P. egedei subsp. grandis (Torrey & A. Gray) Hultén P. egedei subsp. pacifica (Howell) L. A. Sergienko P. rolandii
Treatment appears in FNA Volume 9. Treatment on page 129. Mentioned on page 127, 128, 130.

Stems glabrous or sparsely hairy. Leaves erect, rarely horizontal or ascending, (3–) 10–50 (–75) cm; leaflets (4–) 5–10 (–15) per side, separate, rarely overlapping, teeth (4–) 6–12 (–16) per side, teeth apex acute to acuminate, rarely subacute, surfaces: abaxial with long hairs absent or sparse, on veins, cottony-crisped hairs dense, adaxial glabrous, rarely sparsely to densely hairy. Flowers 1–2.5 (–3.5) cm diam.; epicalyx bractlets narrowly to broadly ovate-triangular, shorter than sepals, entire, rarely 2-fid or dentate; hypanthium patelliform (wider than deep) in fruit; petals not or rarely overlapping, elliptic; carpels (20–) 50–200 (–250). Achenes without dorsal groove. 2n = 28.


Phenology: Flowering summer.
Habitat: Salt and brackish marshes, clay and sandy seashores, maritime drift deposits
Elevation: 0–150 m

Distribution

V9 184-distribution-map.jpg

B.C., N.B., Nfld. and Labr., N.S., P.E.I., Que., Alaska, Calif., Conn., Maine, Mass., N.H., N.Y., Oreg., R.I., Wash.

Discussion

Pacific and Atlantic populations of subsp. pacifica are widely separated geographically but are essentially the same morphologically, except for the high number of achenes in some west coast populations.

Selected References

None.

Lower Taxa

None.

"dm" is not declared as a valid unit of measurement for this property.

0.2 cm2 mm <br />0.002 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
papillate +  and rugose +
green +  and white +
hairy +  and glabrous +
0.07 cm0.7 mm <br />7.0e-4 m <br /> (0.13 cm1.3 mm <br />0.0013 m <br />) +
Reidar Elven +  and David F. Murray +
(Howell) Rousi +
compound +  and simple +
Potentilla pacifica +
25 cm250 mm <br />0.25 m <br /> (30 cm300 mm <br />0.3 m <br />) +
less cordate or reniform +  and narrowly elliptic +
0.5 cm5 mm <br />0.005 m <br /> (25 cm250 mm <br />0.25 m <br />) +
reduced +
free +  and distinct +
hairy +  and glabrous +
Pacific silverweed +
B.C. +, N.B. +, Nfld. and Labr. +, N.S. +, P.E.I. +, Que. +, Alaska +, Calif. +, Conn. +, Maine +, Mass. +, N.H. +, N.Y. +, Oreg. +, R.I. +  and Wash. +
not +  and aggregated +
0–150 m +
0.7 cm7 mm <br />0.007 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
0.3 cm3 mm <br />0.003 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
dentate +, 2-fid +, entire +  and ovate-triangular +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
1 cm10 mm <br />0.01 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
unisexual +  and bisexual +
not +  and aggregated +
deciduous +
on style scar +, hairy +  and glabrous +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.26 cm2.6 mm <br />0.0026 m <br />) +
Salt and brackish marshes, clay and sandy seashores, maritime drift deposits +
stoloniferous +  and short-rhizomatous +
straight +
cottony +  and crisped-cottony +
cottony-crisped +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
0.7 cm7 mm <br />0.007 m <br /> (1 cm10 mm <br />0.01 m <br />) +
0.3 cm3 mm <br />0.003 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
0.2 cm2 mm <br />0.002 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
racemiform open +  and more or less congested +
crassinucellate +
5 cm50 mm <br />0.05 m <br /> (7 cm70 mm <br />0.07 m <br />) +
2 cm20 mm <br />0.02 m <br /> (3 cm30 mm <br />0.03 m <br />) +
0.5 cm5 mm <br />0.005 m <br /> (5 cm50 mm <br />0.05 m <br />) +
0.3 cm3 mm <br />0.003 m <br /> (2 cm20 mm <br />0.02 m <br />) +
bipinnate +, odd-pinnate +, subpalmate +, palmate +  and ternate +
opposite +  and alternate +
50 cm500 mm <br />0.5 m <br /> (75 cm750 mm <br />0.75 m <br />) +
marcescent +
well-developed +
persistent +
cauline +  and basal +
reduced +
10 cm100 mm <br />0.1 m <br /> (50 cm500 mm <br />0.5 m <br />) +
overlapping +  and separate +
elliptic +  and obovate +
linear +  and oblanceolate +
palmate +  and pinnate +
1/4 +  and 1/2 +
incised +, flat +  and revolute +
inferior +  and superior +
clustered +, biseriate +  and superposed +
45 cm450 mm <br />0.45 m <br /> (55 cm550 mm <br />0.55 m <br />) +
2 cm20 mm <br />0.02 m <br /> (45 cm450 mm <br />0.45 m <br />) +
overlapping +
1.5 cm15 mm <br />0.015 m <br /> (2 cm20 mm <br />0.02 m <br />) +
1.5 cm15 mm <br />0.015 m <br /> (2 cm20 mm <br />0.02 m <br />) +
1 cm10 mm <br />0.01 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
free +  and distinct +
0.5 cm5 mm <br />0.005 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
0.5 cm5 mm <br />0.005 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
0.3 cm3 mm <br />0.003 m <br /> (1 cm10 mm <br />0.01 m <br />) +
15 cm150 mm <br />0.15 m <br /> (25 cm250 mm <br />0.25 m <br />) +
1 cm10 mm <br />0.01 m <br /> (15 cm150 mm <br />0.15 m <br />) +
Flowering summer. +
adnate +, free +, connate +  and distinct +
50 cm500 mm <br />0.5 m <br /> (75 cm750 mm <br />0.75 m <br />) +
3 cm30 mm <br />0.03 m <br /> (50 cm500 mm <br />0.5 m <br />) +
Ann. Bot. Fenn. +
not arillate +
0.7 cm7 mm <br />0.007 m <br /> (0.9 cm9 mm <br />0.009 m <br />) +
persistent +
free +  and distinct +
erect +  and spreading +
lanceolate +  and broadly ovate or deltate +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
Endemic +  and Illustrated +
free +  and distinct +
reddish +  and green +
(0.5-)1-5+ times basal leaves +
prostrate +  and erect +
1 +  and many +
flagelliform +
palmate +  and pinnate +
deciduous +
distinct +
papillate-swollen +  and columnar-filiform +
rough-thickened +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
Argentina occidentalis +, A. pacifica +, P. anserina var. grandis +, P. egedei subsp. grandis +, P. egedei subsp. pacifica +  and P. rolandii +
not fleshy-thickened +
Potentilla anserina subsp. pacifica +
Potentilla anserina +
subspecies +
6 +  and 12 +
inconspicuous +
enlarged +
biennial +, annual +  and perennial +
herb +  and matted +