This study was conducted to evaluate the dynamics of endemic populations of mountain pine beetle (Dendroctonus ponderosae Hopkins). In addition, we extended the geographical range of an existing data base recorded in Utah with similar data from Wyoming. This work was accomplished in lodgepole pine (Pinus contorta Dougl. Var. latifolia Engelm.) stands on the Medicine Bow National Forest in south-central Wyoming. Thirty-eight variable-radius paired plots (BAF 10) were measured during the summer of 1987. Host-tree condition and mountain pine beetle infestation characteristics were determined from currently and previously infested trees. Presence and severity of Armillaria root disease and stem pathogens was determined. Tree condition and infestation patterns were similar at this site to those found in earlier studies. Trees selected by endemic mountain pine beetle populations were infested with Comandra blister rust (Cronartium Comandra PK) and root disease (Armillaria spp.). Host-tree condition and mountain pine beetle infestation patterns recorded in this study parallel those identified earlier in Utah and will help land managers identify trees to cut to reduce stand hazard to mountain pine beetle infestation.

This paper presents a broad-based synthesis of the general ecology of the ponderosa pine ecosystem in the Black Hills. This synthesis contains information and results of research on ponderosa pine from numerous sources within the Black Hills ecosystem. We discuss the silvical characteristics of ponderosa pine, natural disturbances that govern ecosystem processes, wildlife habitat and management, various silvicultural methods to manage ponderosa pine forests, and watershed management of the Black Hills.