Also known as: Sweet autumn clematis, sweet autumn virginsbower, leatherleaf clematis, yam-leaved clematis
Origin: Autumn clematis is native to Japan and China. It was introduced to the United States as an ornamental plant and is still widely sold for this purpose.
Description: Autumn clematis is a vine which may grow up to 30 feet. It has opposite, pinnately compound leaves with 3 or 5 unserrated leaflets, each 2-3 inches long. It blooms from late summer into fall. The flowers are white, scented, about 1 inch across, and have 4 petals. Seed-heads are also showy, with long, feathery, silvery-gray hairs.
Distribution: Autumn clematis prefers sun to partial shade but can tolerate moist or well-drained soil and a wide range of soil pH. It is found in forests, forest edges, right-of-ways, and urban green spaces.
Problem: This invasive vine can form a dense tangle, completely taking over its supporting structures, which may be other plants. It can smother native vegetation and compete with native vines for resources.
Control: Hand-pulling of seedlings or small plants may be effective, but care should be taken not to disturb the soil more than necessary. Glyphosate (3%) or triclopyr (3%) may be sprayed onto leaves. This can be done anytime during the growing season, but may be best in the early fall when native plants are dormant, but the target plant is still green and physiologically active. Winter treatment may be possible if green leaves are still present and the high temperature exceeds 50? F. When applying herbicide to a plant with waxy leaves, consider adding 0.5% non-ionic surfactant to the herbicide mix if recommended on the herbicide label.
USE PESTICIDES WISELY: Always read the entire pesticide label carefully, follow all mixing and application instructions and wear all recommended personal protective gear and clothing. Contact your state department of agriculture for any additional pesticide use requirements, restrictions or recommendations.