Cutting Strategies as Control Measures of the Mountain Pine Beetle in Lodgepole Pine in Colorado

Abstract

Efforts to suppress mountain pine beetle (Dendroctonus ponderosae Hopkins) epidemics in Colorado have been carried out since the early 1900s using various methods of treating or removing beetle populations. These methods have slowed the rate of annual tree losses, but have done little to reduce total tree mortality over the course of an infestation, or to reduce the susceptibility of the stands to additional beetle attack. Based on recent research findings that demonstrated the importance of lodgepole pine (Pinus contorta Douglas var. latifolia Englemann) phloem thickness and diameter in mountain pine beetle epidemics, stands in the Middle Park area of Colorado were cut using strategies to reduce stand susceptibility to beetle attack. partial cutting and clearcutting, combined with the logging of infested trees, were used to reduce the inventory of larger-diameter trees. Other factors considered were dwarf mistletoe, comandra rust and visual management concerns. Losses in partial-cut areas have been reduced to 1 to 2 percent of the residual trees, whereas in unmanaged stands 39 percent of the trees have been lost.