Identifying and evaluating pine mortality associated with Ips spp. in Arkansas, Texas, and Louisiana

Pine engraver beetles have historically been recognized as secondary invaders of no detriment to healthy trees. Recent observations of significant pine mortality in Texas and Louisiana appeared to correspond with high population densities of Ips spp. which questions the aforementioned relationship. Three Ips species are found in the southeastern United States, they include: I. avulsus E., I. grandicollis E., and I. calligraphus calligraphus G. They attack all pine species native to this region, usually inhabiting distinct regions of the same tree. A combination of monitoring techniques was used to determine what conditions are congruent with pine engraver infestations. These techniques include roadside surveys, pheromone-baited traps, and comprehensive ground surveys. Sites exhibiting high or low incidence of Ips-associated mortality in Arkansas, Texas, and Louisiana were monitored May-October 2012. Our objectives consist of determining what monitoring results are indicative of high Ips spp. populations and how best to predict varying levels of Ips spp. infestations. Results of this study will benefit forest land managers and silviculturalists who wish to foresee and prevent losses associated with pine engravers when they contribute directly to tree mortality.