Post mortality rate of wood degradation and tree fall in lodgepole pine trees killed by mountain pine beetle in the Foothills and Rocky Mountain regions of Alberta

This project seeks to understand wood degradation in MPB-killed lodgepole pine, which will allow industry to optimize harvesting of at-risk forests. The mountain pine beetle (MPB) can have profound economic and ecological implications for industry and the reforestation of infested forests. One of the main factors to be considered to make the best use of the resources at risk, is the “Shelf Life” of standing dead pine. This determines the correct sequence of harvesting affected stands to ensure maximum benefit of the wood fibre at risk.

Introduction

The MPB can have profound economic and ecological implications for industry and the reforestation of infested forests.  Given that multiple perspectives on natural resource management issues are common, expert prescribed management strategies have to be planned in advance and make the best use of the resources at risk. One of the main factors to be considered is the “Shelf Life” of standing dead pine as it relates to the proper sequencing of harvesting affected stands to ensure maximum benefit of the wood fibre at risk.  The related timber supply analysis would also recognize other ecological variables such as water flow, habitat types and reforestation possibilities.

Shelf life studies already conducted in BC and Alberta will provide the starting point for the study, and there is both research and anecdotal evidence of differences in degradation rates between Alberta and BC.  Furthermore, the sites already studied in Alberta are in the Boreal Mixed-wood Region at the eastern edge of lodgepole pine’s ecological range, and not typical of the Upper and Lower Foothills Sub-regions where most of Alberta’s lodgepole pine exists.

Objectives

The purpose of the proposed study is to enhance understanding of the post-mortality dynamics of wood degradation and tree fall in MPB-killed lodgepole pine in the Foothill region of Alberta. Specific objectives are to:

1. Quantify the relationship between time since death, wood moisture content, and other measures of wood quality and quantity.
2. Determine the influence of region or subregion on the rate of change in wood properties
3. Quantify the effect of site factors (e.g. soil moisture) on the rate of change in wood properties
4. Determine the rate of tree fall across subregions