Yellow-bellied Sapsucker, Sphyrapicus varius, Sapwells
Tidy, uniform rows or columns (or both) of holes on a landscape or woodland tree likely indicates the presence of yellow-bellied sapsuckers in the area.
Yellow-bellied sapsuckers are bark foraging woodpeckers that create sapwells at which to feed. Yellow-bellied sapsuckers make 2 kinds of holes in trees to harvest sap: small, deep, round holes and shallow, rectangular holes that are maintained for sap to flow. They drill neat rows of holes in tree bark, lap up the leaking sap and any insects trapped in the sap, and also eat the cambium of the tree.
Yellow-bellied sapsuckers drill sapwells in more than 1000 species of trees and larger woody plants; pecan, maple, birch, elm, and some oaks are among the preferred species. Typically, the holes do not affect the overall health of the tree or shrub. However, sometimes, if the damage is extensive enough to girdle a stem or the tree itself, there may be tissue death.
Other birds and mammals such as hummingbirds and bats visit sapsucker sapwells to feed on flowing sap.
Contact your local Extension office for management options. Note: The Migratory Bird Treaty Act and Federal regulations prohibit the shooting of sapsuckers.