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Thursday - November 11, 2004

From: Austin, TX
Region: Southwest
Topic: Trees
Title: Bacterial wetwood disease in ash tree
Answered by: Nan Hampton


I have an Ash tree in my front yard. It's about 25 - 30 years old. About 2 months ago, it began to ooze sap from a point where a limb had been pruned, I'd say, about 15 - 20 years ago. So this cut was healed and ok. So the sap is running, it's clear and bubbly. It is surrounded by moths, bees and flies!! When I come home from work, it is hissing. Really, my tree hisses. My son figures it's posessed. My question to you is: what's happening here?!?!?! Is this normal? Any advice is welcome.


A possessed tree, eh? Just in time for Halloween!
I can't be sure but it sounds as if your tree has "bacterial wetwood" disease. This sounds dire, but actually it is not particularly serious. The University of Illinois Extension gives a description of the disease and recommendations for treatment. Colorado State University also has web page information about wetwood disease. In neither of these articles do they mention that the trees "hiss" but they do mention gases produced by the disease that certainly could produce a hissing noise escaping from the tree.

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