Question: I discovered rows of holes on the trunk of one of my new pine trees, and the holes are oozing sap. I have never seen anything like this, and I don’t want the tree to die above all these holes. I thought maybe house caulk would stop the sap, and the tree might heal itself. Can I save the upper part of the tree?
Answer: I think you are noticing the unique feeding pattern of a sapsucker. There are four species of this kind of woodpecker in North America. The yellow-bellied sapsucker is found east of the Great Plains, and the other three can be found in the Rocky Mountains and along the Pacific coast.
They drill shallow holes, about as big around as a pencil eraser, in neat grid patterns on tree trunks. The holes tend to be superficial and not harmful to trees, although they do leak a lot of sap and may look very bad. They usually prefer sticky or sweet trees like evergreens, birch, maple and fruit trees. They come back to the tree and eat any insects stuck to the sap. They also drink the sap. They eat other insects, berries and nuts, especially in the winter.
Other birds also use these trees as feeding sites. Hummingbirds follow sapsuckers north in the spring during migration. Sometimes due to weather conditions, there are not many flowers blooming, so the hummingbirds eat both the sap and the insects. I have seen chickadees, kinglets and nuthatches also take advantage of this food source. If the sapsucker is around, it will chase the other birds away.
Sapsuckers spend the winter in the Caribbean, Southern U.S. and Mexico. They nest in the western mountain states, the Great Lake states, and Canada. They seem to migrate slowly between these areas. I have seen them stick around for a month or more before moving on. The damaged area of the tree trunk may bleed sap for a few weeks but then it dries up.
The rows of scars remain visible for several years. In the northern nesting areas trees can have more damage and may die. The dead trees may eventually be used as nesting trees.
I have seen tree trunks with thousands of holes covering more than 10 feet of height on trees that show no other signs of having problems. Most trees damaged during migration are not seriously harmed by these birds, but you can wrap the trunk with burlap or tree wrap paper for protection. Don’t try to caulk or stop the holes from bleeding. If there are no holes leaking sap now, you can wait until fall to wrap the tree as they may use the same individual trees for several years.
I posted a video showing the yellow-bellied sapsucker and the damage they cause on the Greener View YouTube channel. Check it out to see a pretty, smart and organized bird. If anyone ever calls you a yellow-bellied sapsucker, thank them and take it as a compliment, not an insult.