Uniform Shelterwood Trial to Manage Douglas-fir on Frost Prone Sites (EP 1104.01)

Trial Name: Uniform Shelterwood systems for even-aged Douglas-fir and lodgepole pine stands in the Sub Boreal Spruce (dry, warm) subzones in the Cariboo Forest Region (EP1104.01) (aka Uniform Shelterwood Trial)
Trial Objectives Installation Name Ecosystems Represented Tree Species Silvicultural Systems Tested Post Establishment Treatments
Can Douglas-fir be successfully regenerated using partial retention to reduce frost damage?
Can growth of the residual trees be used to offset mid-term timber supply?
  • Microclimate (frost)
  • Tree regeneration density and growth (natural and planted)
  • Seedfall periodicity
  • Stand stability
  • Vegetation response
  • Small mammal use
  • Overstory tree growth
Uniform Shelterwood Trial SBSdw1
  • Douglas-fir
  • Lodgepole pine
  • Uniform shelterwood using preparation cuts
  • regeneration cuts
  • second regeneration cuts
  • no-harvest & clearcut controls
  • First entry – 1991 – 2 levels of basal area retention (30 & 40 m²) and 2 harvesting methods (feller buncher / hand falling)
  • Second entry – 2001
  • Five levels of BA retention (15, 20, 30 ,40 ,60 m²)
  • Final removal cut in 2011
Comments: Some challenges with mountain pine beetle. The final removal harvest occurred in 2011; beetles no longer a problem.


Publication Topics Publications
General Overview
  • Seedfall, predation, germination and survival
  • Vegetation
  • Natural regeneration densities and growth
  • Planted stock
  • Tree fall
  • Microclimate
  • Stand structure
  • Bark beetles
  • Harvesting costs
  • Damage to regeneration
  • Damage to residual trees
Overstory response
  • Mitchell, S.J. 2001. Summary of shelterwood codominant ten year response in 50% BA removal treatment. Alex Fraser Res. For. Quick Sheet 17.
Small mammals