If you have a smooth-barked tree in your yard, like a birch, maple, apple, or Coast Live oak, you may have noticed tiny little holes along the trunk. If you are like many of our clients, you may have thought they were caused by boring insects. But if the holes are in neat little rows, either vertically or horizontally, they were NOT caused by insects but by birds, specifically sapsuckers like the one pictured above.
But this bird looks like a woodpecker!
It does and that’s because woodpeckers and sapsuckers belong to the same family, the Picidae family. They both have a sharp, pointed beak used to dig out insects and excavate nesting cavities. They have short legs with two backward-pointing and two forward-pointing sharp-clawed toes to cling to trees and have stiff tail feathers to support themselves as they move up and down the trunk of the tree and help brace themselves as they forage for food. Woodpeckers normally work only on decayed and dead wood, whereas Sapsuckers like to target living trees.
Are you sure they are sapsuckers? I’ve never seen them in my tree.
Yes, we can assure you that if you have perfectly arranged rows of holes in your tree, they were produced by sapsuckers. But sapsuckers are migratory. They spend their summers in the Pacific Northwest and winters in California so they are not here year-round, making it harder to see them. Unless you set up a wildlife camera to record the activity, it is difficult to see sapsuckers in the act! However, you might hear them. They make a distinctive drumming sound as they drill holes in your tree.
So why all the holes?
Sapsuckers create holes in trees as a reservoir where the sap can collect. Then they lap up the sap, using their brush-like tongue. These holes also trap small insects and the sapsuckers feast on these unsuspecting dinner guests, or I should say dinner entrée. Other birds also dine at sapsucker holes. Periodically, sapsuckers will enlarge the holes and eat portions of the cambium, inner bark, and fresh sap.
What if I only see a single hole here and there in my tree, was it created by sapsuckers?
No, if sapsuckers have selected your tree for their next meal they will not stop at one hole. They will, at minimum, put at least one neat row of quarter-inch holes. Single holes, scattered in a random fashion, are more likely insects.
Can sapsuckers holes be fatal to my tree?
That’s always a possibility, and sapsuckers that return to the same tree year after year can cause significant damage by enlarging existing holes and weakening the tree to the point of concern where a major part of the tree may die. However, in our experience in the Diablo Valley area, that is more of a rarity than the norm. Plus, it is uncommon that a tree dies because of one specific cause. Tree death is usually a combination of events and/or circumstances. An overabundance of sapsuckers holes, could, in theory, girdle the tree and not allow the flow of water and nutrients up and down the tree. The holes can also attract more harmful insects and/or disease-causing fungus. If the tree is already weakened due to drought, over-pruning, or damage to its roots then the tree may suffer. At that point eliminating the sapsuckers would be helpful.
How do I get rid of sapsuckers once they attack my tree?
First, you need to understand that Woodpeckers (including Sapsuckers) are classified under the Migratory Bird Treaty Act as migratory insectivorous birds and are protected by both state and federal law. This means you cannot kill, poison, trap, or sell these birds and if you do, you could be prosecuted. BUT you can scare them away. Hanging bright and shiny objects in the tree, like old CDs or mylar balloons, might deter the birds, as do loud noises (like banging garbage can lids). You can also use sticky repellents painted on the tree or wrap burlap around sapsucker holes. If you do a google search you will find an abundance of products claiming to deter unwanted pests from your tree. However, be aware that with nature nothing works 100% or is permanent, so if you do manage to scare the birds away once, you may have to do it again.
As always, if you are unsure about any kind of holes in your tree, whether they are caused by sapsuckers or insects, please call our office at (925) 930-7901 to set up an appointment with one of our arborists to evaluate your tree.