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Abstract
Woodpecker damage caused extensive reductions in strength of 50-foot, class-2 utility poles, the amount depending on the cross-sectional area of wood removed and its distance from the apex. Two methods for estimating when damaged poles should be replaced proved to be conservative when applied to results of field rests. Such conservative predictions of failing loads could be used for systematic replacement of damaged poles. Each utility company would have to balance the cost of timely replacement (with resultant loss of some serviceable pole life) against the cost of pole failure and replacement after failure.
Citation
Rumsey, R.L.; Woodson, George E. 1973. Strength loss in southern pine poles damaged by woodpeckers. Forest Products Journal, Vol. 23(12): 47-50