A Management Guide for Invasive Plants in Southern Forests James ...

34Girdling tools can control some invasive tree and shrub species, although this treatment is marginally effective. Bothmechanical and gas-powered girdling tools are available specifically for girdling trees. Other girdling tools includechainsaws, axes, and levered chains. Girdling should penetrate the outer bark to completely sever the inner bark ina ring extending entirely around the trunk. An inch-wide strip of inner bark should be removed to stop flow of sap andnutrients in the stem. Most often a herbicide must be added to the cut area to stop stem and root resprouting. Girdlingmay result in additional hazards as subsequent dead standing trees decay and fall over time; therefore, girdling is notrecommended in high-use areas (along trails or around structures).Ringer tree girdler.Steven T. ManningMechanical MethodsIn many situations, hand labor is unavailable or cost prohibitive and more horsepower is needed. Developed for forestryand land clearing operations, mechanical methods use machines to clear large or dense infestations. Skid-steerloaders, mulchers, and tractors and bulldozers having special attachments have been used to reduce invasive woodyplants. These methods can complement and increase the efficiency of herbicide treatments. Mechanical methodsinclude root-raking attachments on bulldozers for preparing land for construction, landscaping, and other development.Heavy machinery root raking has eliminated privet thickets and kudzu patches (the uprooted plants are subsequentlypiled up and burned). Land clearing methods have also been used in large restoration projects when infestations areextensive and dense, followed by herbicide applications to resprouts and seedlings followed by revegetation with desirableplants. Some equipment, with appropriate attachments, can prepare the site for seeding and tree planting. Mostimportant is using the appropriate size equipment to meet job requirements and minimize damage to soils and streams.Equipment and attachments include:• Skid-steer loaders (modified for kudzu removal)• Four-wheel drive tractors with brush mower, mulcher, harrow, seeder, seed drill, and tree planting attachments• Mulchers (masticators)• Bulldozers with sheer blade, root rake, ripper, harrow, combination plow, tree planter, fire plow, and grubberattachmentsTimely followup with other control methods is essential, because disturbance of the soil creates favorable conditionsfor regrowth from seeds and root fragments. Mechanical removal with larger equipment may not be appropriate innatural areas unless the situation for restoration is critical because of special habitat and restoration plan requirements.