Plant Data Sheet



© Roy Andersen,


Species: Rock clematis; Clematis columbiana


Range: East side of Cascades from British Columbia and east to Alberta, Montana, and Wyoming. (2)


Climate, elevation: Found in valleys to approximately 2,500 meters. (3)


Local occurrence: Open woods and talus slopes.  Not abundant. (5)


Habitat preferences: Dry to moist soils in woods and thickets (3)


Plant strategy type/successional stage: Vine, twines around other plants. (5)


Associated species: Subalpine fir, Beargrass (2)


May be collected as: (seed, layered, divisions, etc.) Seed, Summer softwood stem cutting (2)


Collection restrictions or guidelines: Flowers bloom from June to July (1).  Collect mature plumose achenes when they turn brown in late September and early October(2).  Collect cuttings from healthy field plants in early June (2).


Seed germination: Outdoor stratification for five months.  It must be uncovered, as covered seeds may not germinate (2).


Seed life: Two years (2)


Recommended seed storage conditions: No information available.


Propagation recommendations (plant seeds, vegetative parts, cuttings, etc.): Summer softwood stem cuttings were effective (2)


Soil or medium requirements: Deep, moist soil preferred (3)


Installation form: Plug (2)


Recommended planting density: No information available.


Care requirements after installed (water weekly, water once etc.):  Gradually reduce irrigation prior to installation(2). Plant out in late spring or early summer, after last expected frosts. (3)


Normal rate of growth or spread; lifespan:  Probably slow rate of spread as it is not particularly abundant anywhere. (5)


Sources cited:


1.     Washington Native Plant Society


2.     Native Plants Network



3.     Plants for a Future




5. Wildflowers of the Pacific Northwest from Alaska to Northern California. By Lewis J. Clark.  Edited by John Trelawney.  (Sidney, British Columbia: Gray’s Publishing, 1976).


Data compiled by Deborah Brown, April 13, 2006