Zimmerman Pine Moth

Scientific Name: Dioryctria zimmermani

Zimmerman pine moth is a native pest in the northern half of the United States, east of the Rocky Mountains. It’s larvae burrow into pine trees and other conifers and feed on the sap that is produced by the trees. The burrowing weakens the infected branches and can cause breakage. A heavy infestation may girdle and kill portions of the tree or even the entire tree.

Attacks: Scotch, Austrian, Ponderosa, Mugo and occasionally white pine.

What you will see:

• Oozing globs of resin
• Burgundy larvae underneath the resin mass
• Broken leaders or main branches

Life cycle:

• Moths emerge from in late August through September
• Eggs laid on terminal buds and around wounds
• Larvae feed in fall before entering hibernation
• In April, larvae resume feeding and burrow into bark
• Resin masses appear by late spring and early summer

Cultural Management of Zimmerman Pine Moth

Cultural practices:

• Use low nitrogen fertilizer
• Make sure watering is adequate
• Trees planted too close together are more susceptible
• Shaded trees are susceptible

Chemical management:

• Insecticides can be effective used in the late fall and early spring. Consult with your Arborist for recommended treatments.

An integrated approach

When caring for urban trees it is important to make a complete evaluation of all environmental conditions to accurately diagnose all stress factors and prescribe care based on specific circumstances. This prescriptive care will help your tree meet its full potential.