By Gary Stone, Extension Educator, Panhandle R&E Center, Scottsbluff
Nebraska Extension has been receiving many calls this summer about two weedy vines that have been found in shrubs, trees and fences. If left un-managed, they can smother out shrubs and trees by preventing the tree leaves from photosynthesizing and eventually killing them, especially evergreen trees.
The first is Wild cucumber (Echinocystis lobata), also known as balsam apple or mock cucumber. Wild cucumber is a native plant, an annual with a shallow root system that reproduces by seed. The vines are bright light green in color and will attach and climb on anything they can.
Wild cucumber leaves usually contain five triangular lobes or leaflets. Flowers are small, greenish to white in color. The fruit or seedpod is about the size of a large egg with spines and contains four seeds. Seeds will germinate throughout the summer, especially after a rain. Vines can grow up to 25 feet in length.
The other weedy vine is Virginia creeper (Parthenocissus quinquefolia), also known as wood vine and five-leaved ivy. Virginia creeper, a native perennial plant, can reproduce by seed and will grow back from the existing root system.
The leaves contain five triangular lobes or leaflets, which may turn red in the fall. Virginia creeper is often confused with poison ivy, but poison ivy has three leaflets. The flowers are inconspicuous and green in color. The fruit is a small, bluish-black berry that contains two to three seeds. The woody vines can climb or trail along the ground.
Both plants’ seed serve as food for birds and other wildlife, and that is generally how the seed is spread and ends up under trees and in tree rows. Virginia creeper does serve some ornamental purposes if managed properly and not allowed to get out of control.
Scouting and doing mechanical control
Pulling and hoeing the early germinating plants is the best management option at this time for both plants. Established Virginia creeper with large vines can be cut off near the ground surface and treated with glyphosate as a cut-stump treatment. If practical, established vines of both should be pulled down from the trees.
With all chemicals, be sure to select a product labeled for the site. Read, understand and follow all label instructions when using any pesticide. Create an Integrated Pest Management plan (IPM) combining different control strategies to manage these plants and promote the desired plant community you want.