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Wednesday - June 20, 2012

From: Austin, TX
Region: Southwest
Topic: Diseases and Disorders, Trees
Title: Wound in Monterey Oak from Austin
Answered by: Barbara Medford


I have a 10 year old Monterey Oak that has developed a wound that is secreting a white bubbly substance that has attracted all the bugs, like butterfly's , pill bugs, ants, and several others I don't know the name of. I have sprayed it off with water but the sap comes right back. Can you tell me what to do.


Our first thought on reading this was "Oh, no! Oak Wilt!" However, Quercus polymorpha (Mexican white oak) is (obviously) a white oak, which is not as susceptible to Oak Wilt as the red oaks and live oaks. However, Austin is deep in Oak Wilt country, and we feel you should read all of this Texas Oak Wilt website, and if you feel it is possible that one of the bugs gathered around that sap drip is the nitudulid beetle you should contact:

Eric Beckers
Travis and Hays counties
Texas Forest Service Project Forester
6330 Highway 290 East, Suite 115
Austin, TX 78723

You also should consider how that wound was made to the tree. Construction equipment, lawnmowers, even weedeaters can be the guilty parties. Once the sap has  begun to flow, it can attract a nitudulid beetle that has just visited an infected tree and is carrying the fungus on his body. The best prevention of Oak Wilt is to avoid any damage to an oak tree.


From the Image Gallery

Monterrey oak
Quercus polymorpha

Monterrey oak
Quercus polymorpha

Monterrey oak
Quercus polymorpha

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