Efforts to reduce mountain pine beetle attack in lodgepole pine using verbenone

Mountain pine beetle (MPB), Dendroctonus ponderosae Hopkins, is considered the primary mortality agent of mature lodgepole pine (Pinus contorta var latifolia). Over the past 10 years, a series of studies were developed using verbenone (an anti-aggregant MPB pheromone) to quantify the reduced impacts from MPB . The first study was initiated in campgrounds and administrative areas near Redfish Lake at the Sawtooth National Recreation Area in central Idaho in 2000. After 5 years, MPB had killed 20% fewer of the lodgepole pine trees >13 cm in plots containing verbenone pouches than the untreated plots. When concerns arose about the effectiveness of verbenone over an entire season, a study was began in 2005 near Stanley, ID and Heber, UT using pouches containing a higher quantity of verbenone. There are currently 15 and 25% fewer attacked trees between treated and untreated plots at these two locations, respectively. In 2009, a study was initiated to include sanitation harvesting of MPB-infested trees in the treated plots in addition to verbenone as the standard treatment. These plots were established near Missoula, MT; Fairfield, ID; Alpine, WY; Gunnison, CO; Ft. Collins, CO; and Susanville, CA. These studies will continue until there are no suitable-sized hosts remaining or the current beetle outbreaks subside.