Background
Wild grape (Vitis spp.) is a common name used to describe a group of woody, deciduous perennial vining plants in the eastern United States including V. aestivalis, V. labrusca, V. riparia, V. rupestris, and V. vulpina. Though wild grapes are native species, in abundance, the plants can outcompete overstory trees for sunlight and cause tree limbs to break during winter storms under the additional weight of the vines.
Description
Size
Grape vines can reach up to 50 feet, growing up trees and spreading across the forest canopy.
Leaves
The simple, alternate leaves are toothed, heart-shaped, and often lobed. The leaves vary in length from two to nine inches.
Flowers
Many species of grape are dioecious, having separate male and female plants. The vines produce inconspicuous green flowers in panicles that are pollinated by bees between May and July.
Fruit
The spherical, purple-to-black fruit appears between July and October and can remain on the vine through the winter. Grape fruits range from 1/8th to one inch in diameter, hang in clusters, and are edible. However, their taste varies greatly between tart and sweet. Grape is an important food source for various songbirds, gamebirds, and small mammals and serves as cover for many wildlife species.
Stem
The main stem of a grape vine is brown and shredding in appearance. Smaller stems are dark, thornless and can be hairy in some species. The spiraling structures found opposite of leaves, called tendrils, are used to aid the plant in climbing and support.
Dispersal
Wild grape seeds require full sunlight to germinate. The birds and small mammals that feed on the fruit spread the seeds. Once buried in the soil, a grape seed can lay dormant for many years, waiting for the required conditions to sprout. Grape can also sprout from the roots or the cut vine stumps. These characteristics allow grape to become established after a heavy timber harvest.
Site
Wild grape is often along forest edges, disturbed sites, meadows and fields, streams and rivers, and within the forest interior. Some species prefer rich and moist soils, while others thrive in dry and sandy soils.
Control
Since wild grape provides shelter and soft mast used by many species of wildlife, it is recommended to leave some vines intact. Consider removing plants that are inhibiting the growth of valuable trees and leaving vines on trees of lesser quality.
Chemical
Three chemical herbicides are available to control grape. Dicamba can be applied as a foliar spray, basal bark, or spot application. Fosamine herbicide works as a foliar spray. 2,4-D herbicide can be used as a selective treatment when applied as a stump treatment, basal bark spray, or tree injection. Caution must be taken when using herbicides because they kill non-target broad-leaf under-story plants, seedlings, and saplings.
Mechanical
The preferred method of grape control is by mechanical means. Severing the vines one to two feet above the ground is a very effective control method as long as the vines are growing under a forest canopy. After cutting, the vine will likely resprout. However, the sprouts and entire plant will die within three years if in heavy shade. This method works because grape is shade intolerant. If this method is tried in a young stand when the trees are under 18 feet tall, and the forest floor receives a large amount of sunlight, the grape sprouts may be able to grow back into the tree crowns.
The photograph is used with permission from OSU Extension, Ohio State University.
