Eggs are laid singly on the underside of bark scales, on the trunk or on the branches. Other species of Dioryctria are known to overwinter in a hibernacula 1 and bore into the tree the following spring. Most tunneling occurs beneath a branch or near a wound or site of previous attack. After undergoing what appears to be five larval stages, the larvae pupate in silk-lined chambers in their tunnels or in the pitch mass. Pupation takes place during May, June, and July.
Adults emerge after pupation and egg laying begins shortly thereafter.
Pruning should be avoided during the active flight period of late June through August when egg laying occurs. When branches are removed, pruning should be done in such a way to enhance wound closure. Stress should be avoided to reduce the attractiveness of the trees to the borer. Over-watering, root injury due to road cuts, trenching, compaction, and other factors resulting in stress should be avoided. During exceptionally dry years, watering may be needed to prevent root and needle dehydration.