Sapsuckers at Work
That black and white bird with a red cap and yellow belly is not a traditional woodpecker looking for bugs hiding beneath bark. At work making numerous holes all in a circle around the trunk of your tree is a yellow-bellied sapsucker, who then sucks sap from those wounds.
In early spring, sap migrates to the phloem, the region just beneath the bark, and these birds are eager to suck those juices. Warm days and cool nights make the sap flow hard and furious, and the sapsuckers know it.
Sapsucker damage is easy to identify because the birds make one-half-inch diameter holes that penetrate through the bark into the cambium region. The holes are one-half to an inch apart and circle the trunk, starting from about eight feet above the ground up to where the diameter of the trunk is about six inches. Sapsuckers generally do most of their damage before sunrise and in the evening.
They generally attack smooth bark trees such as magnolia, maple, cherry, apple, crab apple and ash. But I’ve also seen their telltale signs on pine and cedar. The damage they do can be fatal to some species. I’ve seen a southern magnolia so severely damaged that it had to be cut down.
Why sapsuckers attack some trees more than others is not known. I have frequently seen two southern magnolia growing side by side, one showing severe damage while the other showed no damage.
It is not uncommon to see hummingbirds feeding on the sap oozing from the holes as well as bees and wasps when the sapsuckers are feeding in the summer.
Since sapsuckers tend to be skittish, the most effective remedy is to suspend shiny objects to the branches of trees being attacked. Cut 18-inch-long strips of foil six inches wide; twist the foil into long spiral tubes and tie the streamers loosely on branches with cotton string 10 inches to a foot away from the trunk. Space the foil strips two to three feet apart around the trunk. Use cotton string; if you forget to remove it, the cotton will decompose and fall to the ground. Wire or nylon could girdle the branches as they grow larger in diameter.
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