A: This is a common question in the summer and fall and since you are the third person to ask me about this insect, I decided to write about it again. The insect is the psocid, Archipsocus nomas, or tree lice. Trees are occasionally covered with a mat of cobweb-like material and many homeowners call to express concern when they see the trunk and major limbs of their trees encased in a giant silken web, which is completely harmless to the tree. The insects are probably common during most years but are only noticed until population levels are high and the amount of webbing becomes more apparent. Because bark lice cause no damage to the trees, no control is recommended. The webbing, which never extends into the foliage, is quite thin and fragile and will usually disappear in a few weeks.
Psocids are small, soft-bodied insects that resemble aphids. Even though these insects are called bark lice or tree lice they are actually not lice at all. They are not parasitic and they do not harm the trees. In fact, we consider them beneficial because they clean the tree bark of fungi, spores, pollen, lichens, and other debris on the surface of a tree’s bark. Who said nothing in life is free? Here is a perfect example of nature at its best. So do not spray any chemical, they will move onto another tree in a few weeks and best of all, they don’t leave a bill!