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 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.

Vegetation at the Glacier Lakes Ecosystem Experiment Site, a 600 ha research site at 3200 to 3500 m elevation in the Snowy Range of southeastern Wyoming, was categorized and described from an intensive sampling of species abundances. A total of 304 vascular plant taxa were identified through collection and herbarium documentation. Plots with tree species were separated from those without tree species for ordination and classification analyses. Detrended correspondence analysis was used to order plots along major axes of composition variation, which are inferred moisture and topographic gradients. Cluster analysis was used to categorize plots based on composition similarity. The resulting groups were named according to species dominants. We identified and described in detail 4 meadow, 4 thicket or scrub, 3 krummholz, and 2 forest plant associations.

The sterile insect technique (SIT) is an environment-friendly pest control method that fits into area-wide integrated pest management (AW-IPM) programmes. This book describes the principles and practice of SIT, frankly evaluating its strengths and weaknesses, successes and failures. SIT is useful against pests that have considerable impact on plant, animal and human health, and criteria are provided to guide in the selection of pests appropriate for SIT.