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Wednesday - August 01, 2012

From: Austin, TX
Region: Southwest
Topic: Non-Natives, Pests, Trees
Title: Sticky stuff dripping from non-native crape myrtle in Austin
Answered by: Barbara Medford


There is sticky sap-like stuff dropping from the very large crepe myrtle in my yard. The tree has quit blooming. This didn't happen last year when it was so dry; it started after we had all the rain in July. I assume it's a fungus or aphid related somehow to the rain. My question is: should I be worried about the tree? Is there something I should be doing to treat it?


This is a very common complaint this time of year, especially in Austin, and crape myrtles seem to be absolute magnets for aphids. Lagerstroemia indica (crape myrtle) is native to China and therefore not in Mr. Smarty Plants' realm of expertise nor our Native Plant Database. Here is a previous answer on this subject. Avoid herbicides, as they will kill beneficial insects that help control the aphids, but not disturb the aphid eggs that will soon hatch into more aphids. A spray of soapy water will help to wash off aphids and eggs.


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