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Monday - July 30, 2012

From: Austin, TX
Region: Southwest
Topic: Pests, Trees
Title: Something dripping from red oak in Austin
Answered by: Barbara Medford


There is a large red oak outside my apartment. The leaves are shiny and covered with what appears to be oil. The ground underneath is coated with this also. When I parked under the tree my car became covered with oil. It came off easily at the carwash. I don't see any bees or insects and the tree appears healthy. It could be sap, except that it seems to be coming from the leaves. My main concern is that this is possibly an insect infestation.


Because we are hearing about so much dripping from trees, frequently from oaks, that we are going to take a chance and send you links to some previous answers. It seems to be an absolute epidemic in Austin this year, possibly because of the weird weather.

Austin, July 14, 2012

Boca Raton, FL July 10, 2012

These were just the most recent on the subject. We have about 100 questions on aphids in our previous Mr. Smarty Plants questions.

Since this oak is apparently on the grounds at your apartment, you should probably alert the management to have their garden maintenance people examine it. Emphasize, NO HERBICIDE! The herbicide will kill beneficials (like lady bugs) that feed on the aphids and not faze the aphid eggs waiting to hatch into more aphids.


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