Limiting white pine weevil attacks by side and overstory shade in the Prince George Forest Region


  • S. P. Taylor British Columbia Forest Service Prince George V2L 3H9
  • R. D. Cozens British Columbia Forest Service Victoria V8W 3E7


A study was initiated in 1985 to measure the effects of side and overstory shade on attack by white pine weevil and on annual growth in interior white spruce. The study was undertaken in the Prince George Forest Region where the weevil causes extensive damage to plantations of interior white spruce. Annual attack rates decreased significantly with increased brush cover. The treatment with side shade was achieved using narrow strip cuts running east and west. Side and overstory shade also reduced annual growth. Results indicate that up to 6% reductions in annual attack rates could be expected for at least 5 years following treatment but that differences in attack rates between treatments took at least three years to appear.