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Q. Who is Mr. Smarty Plants?

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Thursday - June 11, 2009

From: Arlington, TX
Region: Southwest
Topic: Trees
Title: Sticky white substance from Arizona Ash tree in Arlington TX
Answered by: Barbara Medford

QUESTION:

Our Arizona Ash Tree is producing a white substance that floats down from the tree almost like a snowflake the size of a bb. You cannot see it on the tree/leaves. When it lands on the car, it takes the shape of a tiny pyramid and when you wipe it off, it leaves a greasy residue. What is this and how do we get rid of it? We've had these trees for many years and have never seen this before. Thank you.

ANSWER:

Fraxinus velutina (velvet ash), also called Arizona Ash, is discussed in this USDA Forest Service website Velvet Ash. Among the pests that are mentioned in that article are ash borers and verticillium wilt. Neither of these present the symptoms you are describing. Another possibility is found in this forestpests.org site Woolly Ash Aphid. One more suspect is found in this University of Florida Institute of Food and Agricultural Sciences website Ash Whitefly.

Since we are gardeners and neither plant pathologists nor entomologists, about the best we can do is suggest you look at these websites we have mentioned and see if you recognize any of the symptoms. Then, consider contacting the Texas A&M AgriLIFE Extension Office for Tarrant County. Perhaps there are others in your area experiencing these problems, and they can help you with a diagnosis and, hopefully, a solution. 

 

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