Why Is It a Noxious Weed?
It forms dense infestations that outcompete native plants and can kill small trees. It is listed as a noxious weed in Colorado, where it is reportedly difficult to control. It has the potential to establish in a variety of habitats in Washington.
How would I identify it?
It is a moderately vigorous, deciduous climber or a scrambling shrub that typically forms a mass of stems and grows up to around 27 feet long.
Flowers are single or in clusters of 3 to many. Flowers are on stems up to around 4 inches long and have 4 yellow to yellowish green sepals (look like petals). Flowers to about 1 inch long. Yellow sepals spread outward and may curve back at maturity.
Leaves are opposite on stems, pinnately compound, with five to seven leaflets. Leaflets have variable size, shape and margins.
Stems grow up to 27 feet long and are slender and ridged.
Fruit Seed Description
Seedheads are a rounded cluster of single seeded achenes. Achenes have hairy styles attached and are around 1 to 2 inches long. Seedheads look like pom-poms.
Where does it grow?
Habitats it grows in includes gullies, riverbanks and streambanks, roadsides, open woods, steep hillsides and irrigation canals. Please click here to see a county level distribution map of Oriental clematis in Washington.
How Does it Reproduce?
It reproduces by seed and vegetatively by layering and sprouting from root crowns.
How Do I Control It?
General Control Strategy
In Colorado it is noted to be difficult to control once it is established. It can establish in hard to access areas such as steep slopes with loose rocks, making control of some infestations difficult and expensive.
Colorado recommends hand pulling or digging the plant when the soil is moist, making sure to pull all the roots and carefully bag plant material so as to not scatter seeds.
There are no known biological controls.
For More Information
See our postcard for early detection information about oriental clematis.
See our Written Findings for more information about oriental clematis (Clematis orientalis).