Problems of thinning and small log handling in second growth western hemlock stands with special reference to the research forest on East Thurlow Island

Diminishing virgin timber on the Coast of British Columbia leads to consideration as to how management of the second-growth forests will supply the timber industry with a sufficient quantity of good quality raw material in the future. One of the possibilities would be intensive forest management supported by thinnings. The stands of western hemlock (Tsuga heterophylla (Rafn.) Sarg.), which comprise the largest area on the Coast, may be suited to this treatment because of their advantageous silvicultural characteristics. Little information exists on proper methods of thinning these hemlock stands. In addition, experience in logging methods and means of economically handling small logs are lacking. Among the few experiments which have been established to study thinning of hemlock, one is located on East Thurlow Island where nearly pure stands of hemlock occur. The Research Forest on the Island was scheduled to become an experimental and demonstration area for the study of thinning techniques. Studies under way on that area have shown that the methods used, had limited economic success. Commercial thinning operations turned out to be unprofitable partly because there was no adequate road system available for logging. Thinning problems in general, as well as the particular aspect of thinning western hemlock and the methods of handling small logs are discussed in this thesis to illustrate the basic problems involved in a development plan for the Research Forest. Finally, this thesis presents a general road development plan for the Research Forest area and proposes a preliminary management and logging plan. Through cost analysis it is shown that the basic access road system can be constructed economically during a preparatory period by clearcutting scattered overmature stands. Subsequent thinning experiments can be based on that road network. The approach to these problems is general rather than specific because there are few detailed data available from past experiments.Forestry, Faculty ofGraduat