Herbicides chemically control invasive or unwanted vegetation in home lawns and commercial areas alike. Although a quicker alternative to manual removal, herbicides are harmful for the environment due to high levels of toxins they contain, which is why the Environmental Protection Agency advises careful handling during application and to administer label-recommended amounts only.
Perhaps the most common herbicide application technique is spraying the foliage. Depending on the type of herbicide used, spray it directly over unwanted vegetation or dilute it in water. The University of Florida recommends using sprayers with a pressure range between 20 and 50 psi. Depending on the scale of infestation, some large-scale operators spray herbicide from overhead planes while most farmers use backpack sprayers. It is essential to control the drift of herbicide spray, however, so as not to kill wanted or desirable plants. This techniques is effective for killing small or large infestations as opposed to a few targeted plants. In some cases, multiple foliage applications are required to control invasive plants.
This herbicide technique combines the use of herbicide with an oil to create a mixture applied to the bark of an unwanted tree. The basal application method is successful for trees with smooth barks and trunks less than 6 inches wide. It is essential to treat the lower 1 to 1-and-1/2 feet of the trunk from all sides during the dormant season. This technique is not for older trees, or those with thicker barks through which the oil and herbicide mixture cannot penetrate.
Use this herbicide technique to control larger trees that cannot be controlled with the basal application, or to remove targeted undesirable plants that are planted near desirable ones. In this method, cuts are made around the circumference of the tree with a sharp axe or hatchet that penetrate the thick bark and the nutrient-dense tissue inside. Each cut is made downwards to make room for the herbicide, which will otherwise leak out and render the treatment ineffective. An alternative is to drill holes around the trunk of the tree. Pour 1 ml of herbicide into each cut.
Apply this technique to prevent or reduce the chances of re-sprouts from a freshly cut surface. Mix herbicide with water and apply over freshly exposed surfaces, or with basal oil if applications over cut surface is delayed. Cover only the outer surfaces of larger stumps—larger than 3 inches wide—to kill the living tissue that exists there. Apply herbicide all over exposed surfaces of smaller stumps. Use a paintbrush or sprayer for application.