Biology of \u3ci\u3eDendroctonus murrayanae\u3c/i\u3e (Coleoptera: Curculionidae: Scolytinae) in Idaho and Montana and Comparative Taxonomic Notes

We studied the biology of Dendroctonus murrayanae Hopkins (Coleoptera: Curculionidae: Scolytinae) in lodgepole pine, Pinus contorta Douglas, in Idaho and Montana. The beetle was not a primary agent of tree mortality. Susceptible host trees were physically damaged, had thin foliage, or were otherwise predisposed to infestation. Beetles attacked individual trees, not in groups, near ground level and at low density. Life stages and their behavior are described. Egg galleries were constructed upward and usually had short spurs. Mating occurred in the egg gallery. Eggs were laid in an elongated group, not in niches, in a shallow excavation along only one side of the egg gallery. Larvae aggregated in a communal chamber, feeding side by side, but separated before pupation. D. murrayanae has four instars. One annual generation is indicated, overwintering as larvae. D. murrayanae occurred in some trees with Pseudips (=Ips) mexicanus (Hopkins), Ips pini (Say), and Hylurgops porosus (LeConte) but seldom with the mountain pine beetle, Dendroctonus ponderosae Hopkins. No natural enemy or commensal insect was observed in brood chambers. A new character on the frons is described and the relationship of D. murrayanae and the spruce beetle, Dendroctonus rufipennis (Kirby), is discussed

Electrophoretic comparison of Dendroctonus punctatus LeConte and D. micans (Kugelann) (Coleoptera: Scolytidae)

SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Pine Engraver, Ips pini (Say), in the Western United States

In the western United States, the pine engraver is a significant and frequent pest of ponderosa pine. In some localities it is also an important killer of lodgepole and Jeffrey pines and can be a serious pest in plantations of jack and red pines in the Midwest. In rare instances it may infest pinyon, Coulter, limber, sugar, western white, southwestern white pines, and probably most other pine species occurring within its range

Effects of Climate Change on Ecological Disturbance in the Northern Rockies

Disturbances alter ecosystem, community, or population structures and change elements of the biological and/or physical environment. Climate changes can alter the timing, magnitude, frequency, and duration of disturbance events, as well as the interactions of disturbances on a landscape, and climate change may already be affecting disturbance events and regimes. Interactions among disturbance regimes, such as the co-occurrence in space and time of bark beetle outbreaks and wildfires, can result in highly visible, rapidly occurring, and persistent changes in landscape composition and structure. Understanding how altered disturbance patterns and multiple disturbance interactions might result in novel and emergent landscape behaviors is critical for addressing climate change impacts and for designing land management strategies that are appropriate for future climates. This chapter describes the ecology of important disturbance regimes in the Northern Rockies region, and potential shifts in these regimes as a consequence of observed and projected climate change. We summarize five disturbance types present in the Northern Rockies that are sensitive to a changing climate—wildfires, bark beetles, white pine blister rust (Cronartium ribicola), other forest diseases, and nonnative plant invasions—and provide information that can help managers anticipate how, when, where, and why climate changes may alter the characteristics of disturbance regimes