The Southern Pine Beetle: Biology and Tree Protection

The southern pine beetle is the most destructive native pest of southern pines in North and Central America. This small black beetle occurs throughout the southeastern U.S., north to New England, parts of Mexico, and south to Nicaragua. Females initiate attacks, release pheromones that combine with host odors to attract both males and other females, causing a mass attack. Following mating, females lay eggs beneath the bark along the sides of S-shaped galleries. Low levels of beetle attacks may be thwarted by tree resin defenses, but many beetles can eclipse the tree’s natural defense capabilities. In the southern part of its range, several generations may occur in one year. Successfully attacked trees turn yellow, then red, then brown, and generally occur in tight pockets or "spots". Natural enemies, including insects and birds, can help suppress southern pine beetle populations. Thinning and prescribed burning, when appropriate, are effective silvicultural methods to reduce stand susceptibility to southern pine beetle.Salvage removal (cut-and-remove) and a method called "cut-and-leave" are effective for suppressing expanding infestations during outbreaks.