Burke: Potentilla rivalis

	Potentilla rivalis
	brook cinquefoil, river cinquefoil
Habit	Spreading to erect annual or biennial from a strong taproot and simple crown, strongly pubescent; stem freely-branched and floriferous most of the length.
Leaves	Basal and lower cauline leaves mostly crowded-pinnate with 5 leaflets, the leaflets oblong-oblanceolate, coarsely serrate; upper leaves trifoliate, the leaflets narrower.
Flowers	Inflorescence leafy-bracteate, many-flowered, diffuse, long-pedunculate; calyx cup-shaped, 5-10 mm. broad at flowering, enlarging in fruit, the 5 lobes ovate-triangular, erect, longer than the tubular portion but shorter than the 5 elliptic-lanceolate bracteoles; petals 5, yellow, broadly oblanceolate, rounded, half as long as the sepals; stamens mostly 10, sometimes 15; pistils numerous; styles apical, thickened at the base.
Fruits	Achenes yellow, ovoid-reniform, 0.8 mm. long.

	Potentilla rivalis
Flowering time	May-September
Habitat	Damp soil, especially along rivers and around lakes, ponds, and swamps at low elevations.
Distribution	Occurring east of the Cascades crest in Washington; British Columbia to California, east to central North America, and further east to the northeastern U.S. [WildflowerSearch map] [BONAP county map]
Origin	Native
Conservation status	Not of concern
Sibling taxa	P. anserina, P. argentea, P. biennis, P. breweri, P. drummondii, P. flabellifolia, P. glaucophylla, P. gracilis, P. hyparctica, P. jepsonii, P. newberryi, P. nivea, P. norvegica, P. pensylvanica, P. recta, P. supina, P. villosa
Web links	Local floras: BC, CA, OR, WA Local Web sites: CalFlora, CalPhotos, Flora NW, PNW Herbaria, Turner Photog. WildflowerSearch iNaturalist (observations) USDA Plants Database LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search

Potentilla rivalis

brook cinquefoil, river cinquefoil

Habit

Spreading to erect annual or biennial from a strong taproot and simple crown, strongly pubescent; stem freely-branched and floriferous most of the length.

Leaves

Basal and lower cauline leaves mostly crowded-pinnate with 5 leaflets, the leaflets oblong-oblanceolate, coarsely serrate; upper leaves trifoliate, the leaflets narrower.

Flowers

Inflorescence leafy-bracteate, many-flowered, diffuse, long-pedunculate;

calyx cup-shaped, 5-10 mm. broad at flowering, enlarging in fruit, the 5 lobes ovate-triangular, erect, longer than the tubular portion but shorter than the 5 elliptic-lanceolate bracteoles; petals 5, yellow, broadly oblanceolate, rounded, half as long as the sepals;

stamens mostly 10, sometimes 15;

pistils numerous;

styles apical, thickened at the base.

Fruits

Achenes yellow, ovoid-reniform, 0.8 mm. long.

Potentilla rivalis

Flowering time

May-September

Habitat

Damp soil, especially along rivers and around lakes, ponds, and swamps at low elevations.

Distribution

Occurring east of the Cascades crest in Washington; British Columbia to California, east to central North America, and further east to the northeastern U.S.

[WildflowerSearch map]

[BONAP county map]

Origin

Native

Conservation status

Not of concern

Sibling taxa