Borer in my White Oak - Ask Extension
I have 7 tall, rather spindly white oaks in my back yard that were saved when my home was built 4 years ago. We are delighted to have them a part of ...
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Borer in my White Oak #326962
Asked May 31, 2016, 9:10 AM EDT
I have 7 tall, rather spindly white oaks in my back yard that were saved when my home was built 4 years ago. We are delighted to have them a part of our landscaping. Last summer we noticed some sort of stress/ boring issue going on in two of the trees. We watched it but left it alone. It was suggested that it was perhaps due to woodpeckers. Yesterday we found the hole larger, soft and the back end of this "thing" in it. We remove the thing -- it was not alive , bagged and saved it and snapped a photo. would love some help/advise as our goal is to to keep the trees and make sure they are healthy and strong. Thanks!
Polk County Oregon
Expert Response
Hello,
I think you've found the pupal case of the carpenterworm. The carpenterworm is a caterpillar of a moth, Prionoxystus robiniae. http://www.ipm.ucdavis.edu/PMG/PESTNOTES/pn74105.html.
http://jenny.tfrec.wsu.edu/opm/displaySpecies.php?pn=575
It bores into the wood of living trees, and can be common in oak, but may affect different hardwoods too.
The websites here is the best ones I've seen for management of these, although in this case the insect is gone. It is difficult to manage, but I would keep an eye out for other attacks, and consider the biological control listed in the website if more attacks occur.
I hope this is helpful.
I think you've found the pupal case of the carpenterworm. The carpenterworm is a caterpillar of a moth, Prionoxystus robiniae. http://www.ipm.ucdavis.edu/PMG/PESTNOTES/pn74105.html.
http://jenny.tfrec.wsu.edu/opm/displaySpecies.php?pn=575
It bores into the wood of living trees, and can be common in oak, but may affect different hardwoods too.
The websites here is the best ones I've seen for management of these, although in this case the insect is gone. It is difficult to manage, but I would keep an eye out for other attacks, and consider the biological control listed in the website if more attacks occur.
I hope this is helpful.
