Webs on pear tree are benign

By Audrey Post
MS. GROW-IT-ALL

Q: Our pear tree is just covered with webs, over the branches as well as over the leaves. A second pear tree next to it turned brown and died earlier this year, so it was cut down. This one has a few brown, dead leaves on it but mainly we’re concerned about the webs. What are these webs that seem to be killing our pear trees?

A: We appear to be dealing with two different situations here – and I say “situations” instead of “problems” because one really isn’t a problem, even though those webs might be unattractive.

It sounds as though your other pear tree fell victim to fire blight, a bacterial disease that affects mainly pear trees and apple trees, killing blossoms, shoots, limbs and then sometimes the entire tree. Once the harvest is over on the tree you have remaining, you probably want to prune any dead or dying limbs. If you’re thinking of planting a replacement pear tree, ask your nursery for a variety that is resistant to fire blight. And check to see whether it is self-pollinating.

The webs are caused by psocids (pronounced SO-cids), tiny insects less than a quarter-inch long that form silky webbing, sometimes over large areas of the tree. Underneath the webbing, psocids consume fungi, lichen, pollen and other organic material that is on bark. And our hot, humid weather encourages things to grow on bark. But psocids don’t hurt the tree.

“Once they have eaten everything, they leave the tree unharmed,” said Stan Rosenthal, University of Florida/Leon County forester. “The lesson for us is that not all things on the tree are bad for the tree.”

Plant give-away reminder: Jerry Patton, the Tallahassee gardener with plants to give away including night-blooming cereus, can be reached at 850-878-1321. Several readers requested we run his phone number again.

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