What can I do about the white spots on the leaves of my small, white oak tree - Ask Extension
I've had this small potted Querces Garryana oak tree for about 4 years. This is the first time I've seen small white spots on the leaves. It's defini...
Knowledgebase
What can I do about the white spots on the leaves of my small, white oak tree #844826
Asked August 08, 2023, 8:47 PM EDT
I've had this small potted Querces Garryana oak tree for about 4 years. This is the first time I've seen small white spots on the leaves. It's definitely spread in the last few days. What should I do? Will the tree survive? What is the cause? I've kept it in the shady part of my yard. Was that the cause?
Washington County Oregon
Expert Response
Hello,
That may be caused by a new insect causing issues with Oregon white oak; the oak lace bug:
http://oregonforestry.wpengine.com/2022/11/08/browning-leaves-on-oregon-white-oak-may-be-due-to-damage-from-the-invasive-oak-lace-bug/
And page 26 of this document, which has pictures of the leaf damage: https://www.oregon.gov/odf/forestbenefits/Documents/odf-usfs--2022-forest-health-highlights.pdf
I don't think this will kill your seedlings, but you may want to watch them and occasionally wash the underside of the leaves off to remove any bugs that are there.
That may be caused by a new insect causing issues with Oregon white oak; the oak lace bug:
http://oregonforestry.wpengine.com/2022/11/08/browning-leaves-on-oregon-white-oak-may-be-due-to-damage-from-the-invasive-oak-lace-bug/
And page 26 of this document, which has pictures of the leaf damage: https://www.oregon.gov/odf/forestbenefits/Documents/odf-usfs--2022-forest-health-highlights.pdf
I don't think this will kill your seedlings, but you may want to watch them and occasionally wash the underside of the leaves off to remove any bugs that are there.
Thank you for this information that you've sent. I really appreciate this service!
Juanita