Recognizing the “In-line Borer”

One of the more curious signs on a tree is one or more rows of regular, shallow holes on the trunk. Usually, this is the work of the yellow-bellied sapsucker, a member of the woodpecker family. The sap that wells up at these feeding holes is a significant part of the bird’s diet. Holes are made in spring and fall and may accumulate over time. In contrast, holes made by boring insects do not appear in regular patterns, and they go deeper into the wood.

Figure 1. Sapsucker feeding damage. (Photo: Lee Townsend, UK)

Sapsucker injury rarely kills trees, but many feeding holes may weaken or make trees more susceptible to other problems.

Management Options

Sapsuckers are persistent and hard to discourage. One option is to wrap damaged areas with burlap until the feeding period has passed, then remove it. Visual frightening devices such as hanging pie pans, reflective mylar strips, and fake owls that display movement have had some success at scaring sapsuckers away from a particular tree or area.


By Lee Townsend, Extension Entomologist


Posted in Forest Trees, Landscape Trees & Shrubs