A study was conducted in summer of 1973 to assess impact of fluoride-insect damage on radial growth of lodgepole pine near the Anaconda Aluminum Company at Columbia Falls, Montana. Statistically significant growth losses attributed primarily to the effects of fluorides were found in 40 14 of 17 unmanaged stands for the period 1968-1973 in the polluted area. Radial growth reductions, estimated by comparison with a prediction model, ranged from 0.002 to 0.071 inch. Radial growth loss was transformed to volume loss, averaging 57 board feet per acre per year for the stands examined. Potential height growth losses and observed mortality were not considered. Hand-thinned stands in which growth acceleration should have occurred had not responded as expected. In fact, radial growth losses from 9 to 22 percent were found. Volume losses were not computed for the thinned stands.