Flight of the Mountain Pine Beetle, Dendroctonus ponderosae Hopkins (Coleoptera: Curculionidae: Scolytinae), in Suburban Cheyenne, Wyoming, USA during Summer 2011

The mountain pine beetle (MPB), Dendroctonus ponderosae Hopkins (Coleoptera: Curculionidae: Scolytinae), is a major tree-killing bark beetle that attacks primarily ponderosa pine, Pinus ponderosa Lawson & C. Lawson, and lodgepole pine, Pinus contorta Douglas ex Loudon (Pinaceae), among other pines, across the western coniferous forests of North America (Negron and Fettig 2014). A continental-scale outbreak of MPB occurred from the late 1990s through the mid- to late 2010s, ranging from the southern Rockies north to British Columbia (Jarvis and Kulakowski 2015; Negron and Fettig 2014). In northern Colorado and southern Wyoming, most of the mortality occurred among lodgepole pine but mortality also occurred among ponderosa pine, whitebark pine, Pinus albicaulis Engelm., and limber pine, Pinus flexilis James. Elevated populations of mountain pine beetles across Wyoming reached their highest levels from 2007-2010. Peak mortality in 2009 affected approximately 500,000 ha.Adecade later, populations had markedly declined, with tree mortality occurring on < 200 ha by 2017 (DeSantis 2017).