Use of Chemicals for Prevention and Control of Southern Pine Beetle InfestationsThis article is part of a larger document. View the larger document here.
The southern pine beetle (SPB) is a major threat to pine forests in the Southeastern United States, Mexico, and Central America. In concert with one or more species of southern pine engraver beetles, SPB also may attack and kill pines in residential, recreational, or urban settings. Different control strategies and tactics have been used over the years to try to eliminate beetle problems or reduce resource losses during periodic outbreaks. Insecticides, once the principal means for treating southern pine beetle infestations in forest situations, are now used almost exclusively to protect individual high-value pines in urban settings. Reasons for discontinuation of large-scale insecticide use in forests in the early 1970s included the high cost of chemicals, questionable effectiveness on a landscape scale, and adverse impacts on the beetle’s natural enemies. Although mechanical control methods (cut-and-remove and cut-and-leave) have since replaced chemical control in forest situations, there is still a need and demand for insecticides to prevent bark beetle attacks in residential or recreational areas. Currently, only insecticides containing the active ingredients bifenthrin and permethrin are registered and proven effective for prevention of bark beetles in the Southern United States, and application of these chemicals is limited to uninfested pines in residential or ornamental settings. Methods for applying these chemicals to standing trees for prevention of attacks by the southern pine bark beetle guild are discussed herein, together with safety precautions. Various systemic insecticides have recently been evaluated and found effective for preventing bark beetle attack in standing trees. Those containing the active ingredient emamectin benzoate or fipronil show the most promise, and EPA registration of these chemicals is expected. The advantages and disadvantages associated with the use of topical sprays and systemically injected insecticides to treat SPB populations or prevent the colonization of high-value trees also are discussed in this chapter.