Zimmerman Pine Moth – How to Protect your Pine Trees

Although the Zimmerman Pine Moth isn’t known to cause as much damage as the Mountain Pine Beetle or Emerald Ash Borer, it does have the potential to kill off or injure your pine trees.  If you have a Zimmerman Pine Moth problem the best solution is to have your tree sprayed by a professional.

zimmerman pine moth
(Zimmerman Pine Moth)


The symptoms of a Zimmerman Pine Moth infestation are:

  • Yellowing or dying off of new growth at the tops of pine trees.
  • Infested branches that wilt and curve in a downward direction, making the shape of a hook.
  • If untreated you will see brown branches that break off easily during a storm or hard wind.

For early detection, you should be able to see golf ball-sized resin masses that are white or grey.
Pine trees are most vulnerable under certain conditions.

  • If they border on open space or golf courses.
  • If they are located within areas of Zimmerman Pine Moth infestation.
  • If they are stressed due to lack of water.
zimmerman pine moth
These golf ball-sized resin balls indicate Zimmerman Pine Moth infestation


ZPM was found in the U.S. in 1879.  Since that point, we have seen it in 23 states but largely in the northern part of the country.
Like other aggressive insects, the ZPM prefers to attack weakened or stressed trees.  The best way to prevent insect infestation is by taking care of your trees before anything happens, but once the moth has infested your tree the only tree-saving option is to have your tree sprayed.
The times to spray for ZPM control are during the months of August and September.
Larvae of the Zimmerman Pine Moth damage trees by tunneling under the bark and creating large wounds.  The damage to the tree is usually around the branch crotches.
Zimmerman pine moth females will lay eggs near the wounds or pitch mass borers that were previously made.  In roughly a week the eggs will hatch and the larvae will feed for a brief time before they get ready for winter.