Rosaceae

Description

A low-growing, hairy, widely-spreading, perennial herb from long runners which grows in wet, alkaline areas.

At a glance

• Plant Type: Herb.
• Distribution: This plant grows from Alaska to California (including British Columbia) and east to the Rocky Mountains, Great Plains, Great Lakes region, and northeastern North America. This plant grows on both sides of the Cascades crest and at the coast in Washington.
• Height: This plant grows up to 16 inches (40 cm) in height.
  Flowers: Single yellow flower grow on leafless stalks up to 8 inches (20 cm) in height. The flowers are oval, contain 20 to 25 stamens and numerous pistils, and the petals grow approximately 1/2 of an inch (8 to 12 mm) in length.
• Leaves: Upright basal leaves grow up to 16 inches (40 cm) in length. The leaf blades can be greenish on the upper surface or whitish silky-woody on both surfaces. The leaflets are combination of large and small with 15 to 25 leaflets on each stem.
• Fruits: Flattened oval achenes, light brown in color grow less than 1/8 of an inch (2 mm) in length.
• Notable features: The name "Silverweed" refers to the silvery-gray appearance of the plant. Silverweed patches were often owned by certain tribal chiefs, especially among the Nuu-chah-nulth, Kwakwakawakw, and Haida Native American tribes.
• Subtaxa: Two subspecies of Potentilla anserina are native to Washington.
  • Potentilla anserina ssp. anserina has epicalyx bractlets which are equal to or longer than the sepals. The achene has dorsal ridges or veins. This subspecies grows in mudflats, grasslands, and along shores and dunes. This subspecies grows from Alaska to Mexico (including British Columbia), and east to the Rocky Mountain states, and across the norther U.S. and Canada to the Atlantic coast; also found in South America. In Washington, this subspecies grows on both sides of the Cascades crest and at the coast. The common names for this subspecies are Silvery Cinquefoil and Common Silverweed.
  • Potentilla anserina ssp. pacifica has epicalyx bractlets which are shorter than the sepals. The achenes are smooth, and do not contain dorsal ridges. This subspecies grows in salt marshes, estuaries, and dunes. This subspecies grows from Alaska to Mexico, and east across North America to the Atlantic coast. In Washington, this subspecies grows west of the Cascades crest and at the coast. The common name for this subspecies is Pacific Silverweed.
• Synonyms and Misapplication:
  • Potentilla anserina ssp. anserina
    • Argentina anserina var. concolor, Potentilla anserina var. anserina, Potentilla anserina var. concolor, and Potentilla anserina var. sericea
  • Potentilla anserina ssp. pacifica
    • Potentilla anserina var. grandis, Potentilla egedii ssp. grandis, Potentilla egedii var. grandis, and Potentilla pacifica
    •  Misapplication: Potentilla anserina ssp. egedii

Ethnobotany

The roots were used as food by nearly all of the coastal Native American tribes. Silverweed has two types of roots: short, curly roots near the surface, and long, fleshy taproots. These roots were steamed to remove their bitter flavor. Among the Nuu-cha-nulth tribe, silverweed roots were second only to bracken rhizomes as a root vegetable. In Kwakwakawakw tribal tradition, the men cooked silverweed roots at feasts. Layers of curly, long roots were steamed over hot rocks. The tribal chieftains and high-ranking persons at the long roots and the other male tribal members at the curly roots. Leftovers were taken to the female tribal members. The roots were collected and boiled by the Haida Native American tribe, who drank the tea as a purgative. The roots were mixed with other herbs and used for medicinal preparations. The Kwakwakawakw Native American tribe boiled the roots and mixed them with fish oil and applied them as a poultice. They also pressed the roots and applied to the juice to inflamed eyes. The Blackfoot Native American tribe of Alberta used the runners as ties for leggings and blankets.

References

• CNPS Calscape: https://calscape.org/loc-California/Potentilla%20anserina%20(Silverweed)
• Hitchcock CL, Cronquist A. Flora of the Pacific Northwest: An illustrated manual. 2nd ed. Giblin DE, Legler BS, Zika PF, Olmstead RG, editors. Washington, D.C., DC: University of Washington Press; 2018. Page 203.
• Pojar, J and MacKinnon, A. 1994. Plants of the Pacific Northwest Coast: Washington, Oregon, British Columbia and Alaska. Vancouver (BC): Lone Pine Publishing.
• Starflower Foundation Image Herbarium and Landscaping Pages, 2007.
• WTU Image Herbarium: https://biology.burke.washington.edu/herbarium/imagecollection/taxon.php?Taxon=Potentilla%20anserina 

Page Editors/Authors

• Gerald B. Stanley

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