The Costs And Benefits Of Tree Improvement Programs

Three tree improvement programs were analyzed by break-even, cost-benefit technique: one for ponderosa pine in the Pacific Northwest, and two for Douglas-fir in the Pacific Northwest-one of low intensity and the other of high intensity. A return of 8 percent on investment appears feasible by using short rotations or by accompanying tree improvement with thinning. Interest rates, length of rotation, the inclusion of thinnings, and site index had greater effects on profitability than program design. Large breeding zones improved profitability, although they incur the biological risks of nonadaptation to local conditions and loss of local genetic resources. Increasing orchard seed yield affected the results only slightly unless the planting program could be expanded, which is equivalent to increasing the size of the breeding zone. If the increase in seed yield merely reduced the required acreage of seed orchard and associated costs, the financial results improved only slightly.

Review of current literature establishes that most authors believe that tree improvement expands production, although some point out drawbacks and alternatives. Both softwood and hardwood improvement programs have been analyzed. The authors used various models, economic assumptions, and standards of measurement, but available data were limited. Future models shouId attempt to be more eclectic.