As you might guess, mile-a-minute vine was named for its speedy growth, with the vines reaching 15 feet in a single growing season. Another name for it is "Asiatic tearthumb" because the vines are lined with hooked barbs that catch on skin and clothing. It's easy to identify because the leaves are shaped like equilateral triangles. The stems are often reddish and surrounded by cup-like leafy structures. Small spikes of colorful metallic-blue, pea-size fruits are held above the vines.
Mile-A-Minute was accidentally introduced to the United States from eastern Asia. It began to be noticed in the wild in the 1930s and has mainly established in the Mid-Atlantic and northeastern United States. You will find it growing along streams, roadsides, in young or recently cut forests and in thickets.
Mile-A-Minute quickly grows over small trees and shrubs, slowing their growth. Along stream sides it can cover the ground preventing rare wetland plants from growing. It becomes a problem for hikers as it scrambles across paths snagging ankles.
Since mile-a-minute is an annual vine and has relatively shallow roots, it can be pulled out and the vines rolled into balls. Wear gloves, long sleeves and long pants to avoid the thorns. Plants should be pulled before they set seed in early summer. If it is growing somewhere where it can be mowed, mowing close to the ground will remove flowers and prevent fruiting. For large infestations, herbicides containing glyphosate, such as Roundup® brand Weed & Grass Killer products, can be sprayed on plants before seeds form. The seeds will remain viable in the soil, so be sure to check areas that have been cleared for several years in spring for new plants.
The seeds are often carried to new sites through the movement of soil. If construction equipment or fill dirt is brought to your home, monitor the disturbed areas for signs of Mile-A-Minute. Birds, small mammals and ants also disperse the seeds. Often plants will establish under a favorite perching area or near an ant nest or burrow. Mile-A-Minute needs some sun to grow, so maintaining healthy woodlands will help prevent it from establishing in a forest.
All photos courtesy of Sylvan Kaufman. Article by Sylvan Kaufman. Dr. Kaufman is a writer of popular scientific and gardening articles. She is also an ecological consultant.