Ranunculus occidentalis Nutt.

Western Buttercup

Brother Alfred Brousseau 1995 Saint Mary's College of California (courtesy of CalPhotos)

Range: South-western North America - British Columbia to California and Nevada.


Climate, elevation: Sea level to 1800 m, Hardy to 0C, 10-50 inches of rain, Shade tolerant, Moderate salinity tolerance, Fire adapted

Local occurrence (where, how common): Common

Habitat preferences: Vernally moist ground and grassy slopes in Wetlands, Meadows, Foothill Woodland, Yellow Pine Forest, Coastal Prairie, Red Fir Forest and Lodgepole Pine Forest


Plant strategy type/successional stage: Perennial, Mid successional until canopies close


Associated species: Festuca romeri, Eriophyllum lanatum, Lomatium utriculatum, Achillea millefolium, Prunella vulgaris, Agrostis capillaries, Viola adunca var. adunca, Luzula comosa

May be collected as: Seed in late summer

Collection restrictions or guidelines: Unlisted


Seed germination: Sow at 18-22C (64-71F) for 2-4 wks, move to 5C (23F) for 4-6 wks, move to 5-12C (41-53F) for germination

Seed life: Short Viability


Recommended seed storage conditions: Cool and dry, does not store long.

Propagation recommendations: Seed - sow spring in a cold frame. When they are large enough to handle, prick the seedlings out into individual pots and plant them out in the summer.

Soil or medium requirements: Excellent drainage is necessary in cultivation. Need dry summers in cultivation.

Installation form: Success has been had plugging in prairies on the San Juan Islands.

Recommended planting density: Naturally not in dense patches, but does not spread colonially or rapidly from seed. Good survivorship from plugs. Dense planting is not necessary.


Care requirements after installed: Plants respond well to controlled burning. Supplemental irrigation may be necessary.

Normal rate of growth or spread; lifespan: Non-rhizomatous, slowly spreads by seeds

Sources cited:

-         Calflora: Information on California plants for education, research and conservation. 2006. Berkeley, California: The Calflora Database [a non-profit organization]. Available: http://www.calflora.org/. (Accessed: Apr 23, 2006)

-         Clothier, Tom. http://tomclothier.hort.net/ (accessed Apr 25, 2006)

-         Dunwiddie, Peter W., Management and Restoration of Grasslands on Yellow Island, San Juan Islands, Washington, USA, From: http://conserveonline.org/docs/2002/04/Management_and_Restoration_of_Grasslands_on_Yellow_Island2.doc  

-         Hickman, J.C. (editor) 1993, The Jepson Manual. Berkeley, California. 1400p.

-         Klinkenberg, Brian. (Editor) 2004. E-Flora BC: Electronic Atlas of the Plants of British Columbia [www.eflora.bc.ca]. Lab for Advanced Spatial Analysis, Department of Geography, University of British Columbia, Vancouver.

-         Plants for a Future, Rich Morris 2004, England and Wales, http://www.pfaf.org/database/plants (Accessed Apr 25, 2006)

-         USDA, PLANTS database. http://plants.usda.gov

-         Washington State Department of Natural Resources, http://www.dnr.wa.gov/nhp/refdesk/communities/pdf/fero-seri.pdf. (Accessed 4/25/06)

Data compiled by: Sierra Smith 4/24/06