Diazinon should control the problem. Zimmerman pine moth larvae bore into the trunk. The only outward symptoms may be death of parts of the tree or masses of hardened pitch on the branches. No chemical control is listed The larvae of pine weevils feed on the sapwood of the leaders. The leader is killed and the shoots replacing it are distorted.
First symptoms are pearl white drops of resin on the leaders.
The leaders die when the shoot is girdled as adults emerge in August. Prune out and burn infested terminals before July 15. Visuals associated with this text. This information is for educational purposes only. References to commercial products or trade names does not imply endorsement by MSU Extension or bias against those not mentioned.