Height Loss from White Pine Weevil

Two approaches were used to obtain data on height loss, necessary for construction and use of site index curves, caused by white pine weevil in eastern white pine. Comparison of normal leader and lateral growth showed that height loss for the year or years prior to weeviling may amount to about 40 percent of the growth of each leader killed back. Relatively more height loss occurs when leader growth is especially good. Comparison of current growth of healthy and weeviled internodes in felled trees indicated a total height loss equal to about 60 percent of the average leader growth for each weeviling. A good prediction equation for height loss in older stands was not found, but minimum height loss appears to be 60 or 70 percent of average growth for each weeviling.