|The original project goal for the Skull Mountain Project was to investigate the effects of natural disturbance regime (frequent fire return cycle) on stand structure, and ultimately on biodiversity (indicated by mule deer, bird communities and vegetation). Forest management guidelines for dry Douglas-fir dominant stands were intended to be developed based on the results. The original project goals have not changed, however, the wildfires of 2003 necessitated changes in the project plan. Prior to the fires, operational harvest trials intended to best mimic the natural disturbance regime had been completed. The prescription trial was retention of 10-25 stems/ha including all veteran trees, with the balance from the dominant canopy, applied to 40-90 ha cutblocks. At the time, the silviculture prescriptions were designated as clearcuts with reserves or seed tree retention. Up to 5 years’ post-treatment mule deer winter range and vegetation data had been collected (first harvest in 1998, last winter sample 2002-03). After 2003, the project plan was adapted to test the effects of the actual fire. Mule deer winter range and vegetation were compared pre and post-burn in three treatments: original operational harvest, uncut forest (control), and post-burn salvage with large tree retention (pre-burn was uncut). The post-burn phase of the project, however, would best be managed in terms of planning if the pre-burn phase is fully understood through completion of analysis; this was recommended in the PWC audit of the project in spring 2005. Therefore, the pre-burn phase of mule deer winter range and associated vegetation analysis and interpretation was to be completed, with application of the results, where necessary, to the current project plan, including establishing timelines for project completion. The fires of 2003 occurred <5 years post-treatment. As a result, full treatment effects were likely not realized, and analysis simply may not yield statistically significant results. Nevertheless, management guidelines for best levels of retention and cutblock design to provide mule deer winter cover and forage were to be developed based on the results, where possible; these management recommendations are intended to be specific to dry Interior Douglas-fir forests (IDFxh2 and dk2, in particular).|
prepared by Astrid M. van Woudenberg.