What Herbicides to Use for Thick Vines

Features

• Thick vines are hard to kill. Vines such as kudzu, poison ivy and trumpet vine grow above ground and underground. When these vines are chopped down, they grow back from the stump and from the roots. Thick vines, which can be years or decades old, are supported by an extensive root network that puts up shoots renewing the vine’s invasive efforts. Thick vines grow like small trees and are resistant to common removal methods such as hand-pulling or digging.

Herbicides

• Common herbicides for vine control contain the active ingredients glyphosate or triclopyr. These herbicides are systemic and, absorbed by foliage, stems or roots, the chemicals disrupt the plant metabolism so that the entire plant dies. These herbicides target brush and vines, woody plants requiring direct and sustained application. Because these herbicides are applied only to the target vegetation, they do not harm nearby plants or travel through the soil to other plants. Herbicides designed for grasses and weeds are not effective in eradicating thick vines.

Application

• Foliar spraying slows the growth of thick vines. Applied to the leaves, the herbicides are absorbed and carried into the plant. On well-established vines, more effective methods include both mechanical and chemical techniques. Thick vines are off cut at the base, like a tree, and the stump treated directly with glyphosate or triclopyr that travels into the roots. In basal spraying an herbicide such as triclopyr amine, an oil-soluble formula, is mixed with oil and sprayed on the lower vine trunk. This mixture penetrates the vine and injures or kills the vine. A thick vine can be treated with frilling or girdling, which means using a hatchet or other tool to cut into the tough vine bark and expose the inner vine layers. An herbicide such as triclopyr ester, a water-soluble formula, is mixed with water and squirted into the cuts to be absorbed and carried through the vine.

Tips

• Herbicides containing triclopyr or glyphosate ingredients are effective when used as directed and are readily available at home center and farm supplies. Foliar applications require repeat applications due to new growth and the multiple leaf layers on established vines. Stump applications require added cutting and herbicide applications when suckers appear. Because thick vines are woody, herbicides are absorbed slowly and work over time, wilting and stunting the vines until they die weeks later. Several seasons may be needed for complete control. Other herbicides such as tebuthiuron and picloram control vines and shrubs but are restricted to licensed application.