Harmful Insects

Zimmerman Pine Moth

Pines planted in Minnesota are susceptible to a destructive stem-boring pest called the Zimmerman pine moth. The larvae of this insect damage trees by tunneling just under the bark of at the point where main branches meet the trunk. This activity damages the vessels that carry water and nutrients throughout the tree. The tunneling also weakens branches, which eventually fall from the trunk or are broken by heavy snows or high winds. The top of the tree or branches may be killed when the tunneling cuts off the supply of water and nutrients to those sections of the tree. Infested trees become stunted and deformed after repeated attacks; heavily attacked trees eventually die. Wood-boring insects are particularly difficult to control. Insecticidal sprays are usually necessary, but they should not be used alone.

To learn more see the attached information sheet by clicking the PDF icon below.