Adult white pine weevils. Photo by Dave Powell, USDA Forest Service, Bugwood.org
"Shepard's hook". Pruning before the first whorl of branches is reached makes it easier to train a new leader. Photos by Whitney Cranshaw, Colorado State University (top), E. Bradford Walker, Vermont Department of Forests, Parks and Recreation, Bugwood.org (both pictures on bugwood).
Larvae tunnel just under the bark, eventually girdling the leader and killing it. Photo by E. Bradford Walker, Vermont Department of Forests, Parks and Recreation, Bugwood.org.
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