Description:
Mammal and bird damage recorded on Douglas-fir and ponderosa pine
plots-randomly established in Oregon and Washington during 1963-64, then
observed for 5 to 10 years-was evaluated for impact on survival and growth.
In all, 194 plots were installed, and 10 of the 110 seedlings on each plot were
caged to protect them from animals. All trees were examined after planting
and after bud burst each year for 5 years. A selected sample of 45 Douglas-fir
plots was observed another 5 years for long-term patterns and effects of severe
plantation damage. Survival and growth were compared for caged and uncaged
trees. The agents, kind, amount, and distribution of animal damage were
evaluated by state, by subregion, and by relation to site features. Results
indicate that stand damage in plantations exposed to heavy animal use,
especially during seedling establishment, warrants expenditure for protective
measures.