Opuntia, commonly called prickly pear, is a flowering plant with species native to the Southwest and invasive species from Central America and the West Indies. These plants can have a horizontal growing pattern along the ground or vertical growth which can reach heights in excess of six feet. No matter the species, prickly pear adversely affects grazing areas by restricting the growth of desirable forage, as well as, preventing cattle from grazing due to spines on the leaves of the pears.
Varying methods exist to physically control prickly pear. However, complete physical removal is difficult since prickly pear spreads both by vegetative segments and by seed. If using physical methods, all parts of the plant need to be extracted. If any vegetative remnants exist, they need to dehydrate or regrowth is likely to occur. Since viable seeds will remain, follow-up herbicide application must be used to control the regrowth and germination of seeds. While physical removal is the quickest means of plant reduction, regrowth should be expected.
Chemical control is the most effective means of eradication. Triumph 22K, is a highly recommended herbicide. It contains the active ingredient picloram which is a restricted-use product that requires an applicator’s license. Cleargraze, an unrestricted product, is another herbicide option that contains the active ingredients Fluroxypyr and Triclopyr. Both Triumph 22K and Cleargraze can be used for individual plant treatment at a rate of 1.0% v/v, however, a broadcast treatment requires the use of Triumph 22K at 32 ounces per acre. When spraying, complete pad coverage is extremely important, especially during individual plant treatment. The use of an approved adjuvant is needed to ensure penetration on the waxy pads. Large patches of prickly pear pose problems with ground application. If an aerial application is used, it is most beneficial to apply in the winter months, when the canopies are absent, which can minimize tree damage and allow for maximum coverage of the prickly pear. With chemical treatments, visible activity and overall control will be slow to show and a time period of two to three years may be necessary to reach a high level of mortality.
As a general rule, once the prickly pear population reaches a density greater than 400 plants per acre, it becomes more economical to apply a broadcast treatment instead of doing individual plant treatments. A broadcast treatment application is recommended during the months of January through March when there is no tree canopy above the plants to intercept the herbicide. This also allows for broadleaf weed control.
Contact your local Natural Resources Conservation Service (NRCS) office for information regarding the cost-share programs that are approved for Triumph 22K® applied broadcasts.
