|WHAT HAPPENED TO THIS TREE?|
|PERFECTLY HEALTHY NEIGHBORING TREE|
|WAS IT LAWN HERBICIDE?|
|YELLOW SHAFTED FLICKER DAMAGE|
|...IN A DOUBLE ROW, GIRDLING THE TREE|
The sudden withering of all the leaves on a city tree, located just off the northwest corner of Rittenhouse Ave. and Broad street, has left me mystified and groping for answers.
My first assumtion was that it was herbicide drift from nearby lawns, but checking with neighboring property owners I pretty well ruled that out. Actually it looked more like fire blight than anything else, but the little leaf linden (Tilia cordata) is not be susceptible to that disease. To make the mystery even deeper, another perfectly healthy linden is just thirty feet to the north of the affected tree.
Next I had the utility company check for a gas leak in the area, which would cause that type of damage, but they assured me there were no leaks.
I thought perhaps hot diesel exhaust from an idling tour bus or delivery truck might be the culprit, but it is not a spot where a large vehicle would ordinarily park and idle.
Finally I took a second or third, much closer look at the tree trunk, and here is what I believed happened to the tree: I found woodpecker holes, all in a row, bored all around the trunk, at several evenly spaced levels. I have seen a lot of yellow shafted flicker damage but never saw a flicker or sapsucker actually kill a healthy tree, but this looks like pretty severe girdling of the cambium just beneath the bark (which is rather thin) and we had a spate of unusually hot weather about two weeks ago, and I believe the tree was inordinately stressed because of the girdling holes in the trunk. Unless I see further evidence of some other factor, I am calling the case closed. I will not, however, take the tree down now, but give it a chance to repair some damage next spring.
Woodpeckers of all kinds can do a lot of damage to trees and even buildings if their depredation becomes a habit to them. Mostly they are looking for grubs under the tree bark, but flickers and sapsuckers actually drink the tree sap from the holes they drill. One can put hardware cloth or burlap around a tree that is being damaged, but the birds should not be molested, as all woodpeckers, including flickers and sapsuckers, are protected by state and federal law, and one could face a stiff fine for harming one, which seems a little draconian to me. After all, if a bird insists on damaging an equally environmentally and economically important tree and it is protected by law, I protest that it should also be illegal for the bird to kill the tree. Perhaps it could be sent to jail. Won’t happen I guess.