HOSTS: Oaks, maples, tulip trees, cherry trees, willows, and pines.

SYMPTOMS: Staining along trunk or branches, fras (fine sawdust), sap on trunk, and dieback in canopy.

DESCRIPTION: Borers are the larvae of beetles or moths.  Females lay their eggs throughout the summer season in the bark.  The larvae tunnel through bark, sapwood and heartwood as they feed.  This disrupts the flow of nutrients and water through the vascular system.  Dieback in the canopy soon results.  Trees stressed by drought, poor growing conditions, mechanical damage, etc. are particularly susceptible to infestation.  Borers often kill the tree. 

TREATMENT: Timing for treatment varies by species of borer.  New advances have been developed that are not only more effective, but also reduce the number of treatments, reducing costs.