MW-01-039

Influence of Lodgepole Pine Stand Density on Crop Tree Productivity and Wildlife Habitat Diversity
Sponsor: 
Millar Western Forest Products Ltd.
Lead Researcher: 
Applied Mammal Research Institute, Summerland, British Columbia
Body: 
This study was designed to test the hypotheses that large-scale pre-commercial thinning of lodgepole pine over a range of stand densities enhances productivity and old growth features of lodgepole pine crop trees, stand structure attributes, and species richness and diversity of small mammal communities.

The study areas in British Columbia were located near Penticton, Kamloops, and Prince George. Each study area included three stands thinned in 1988 to densities of 500 (low), 1000 (medium), and 2000 (high) stems/ha, as well as unthinned juvenile pine and old-growth pine stands used for comparative purposes. Understory vegetation was measured in 1990, 1993, and 1998, and stand structure was measured in 1998. Small mammal populations were sampled intensively in 1990, 1991, and 1998.

The results suggest that tree diameter growth, tree crown volume, herbaceous vegetation, multilayered coniferous stand structure, total plant species diversity, and species richness and diversity of small mammals will be enhanced by heavy thinning of lodgepole pine stands to = 1000 trees/ha. The findings conclude that appropriate thinning regimes may contribute to ecosystem management and emulation of natural disturbance patterns.