Project Title: Determining susceptibility of young pine plantations to the mountain pine beetle, Dendroctonus ponderosae, and manipulating future stands to mitigate losses.

Project Purpose and Management Objectives: This project will determine implications and impacts of the mountain pine beetle (MPB) in regenerated pine (natural and plantations) throughout the interior of British Columbia. Results from this study will provide the basis for a susceptibility rating system for present and future plantations and will enhance existing management strategies in shaping our future forests. The data provided by this project will be directly incorporated into Timber Supply Reviews (TSR’s) for interior Timber Supply Areas (TSA’s). This study will elucidate the potential differences between MPB impacts to young stands within the core (older part of the outbreak) versus the newer areas of the outbreak. Risk factors, MPB dispersal patterns, young stand attributes and availability of mature host material will be key components in determining a revised susceptibility matrix. By quantifying the level of current and past attack as it relates to outbreak history and adjacent conditions (MPB levels, species mix in adjacent stands, level of harvest and others) we may be able to implement treatments or strategies that reduce the future impact to other young stands. This project will address whether current mortality is solely the result of extreme beetle pressure, or whether tree and stand attributes have changed to produce more susceptible hosts. Drought stress or climatic change could also be influencing factors (Safranyik 1978). Climate data collected in a representative mature and young stand will give insight into any differences that may affect brood success or mortality in these two settings. Results from this project will be directly applied to protecting and mitigating future damage to high value stands such as seed orchards as well as young stands in the working forest.