Knowledgebase
Oak Tree leaves #871664
Asked June 05, 2024, 9:06 AM EDT
Larimer County Colorado
Expert Response
This looks like oak leaf blister, which is a common fungus that the group of white oaks tend to get. Fortunately, it just looks bad, but rarely causes harm to the tree. The oak you have appears to be a bur oak, which is a type of white oak.
Unfortunately, it's too late to do anything, as preventative fungicides are the only option and must be sprayed during budbreak.
Here's more information from Utah State: https://extension.usu.edu/planthealth/ipm/notes_orn/list-treeshrubs/oak-leaf-blister
This fall, rake up the leaves and throw them in the trash. This disease is most common during wet springs, which we didn't really have, but perhaps the temperatures and timing were "just right" this year.
Randall D Howard, CPL
On Jun 5, 2024, at 7:06 AM, Ask Extension <<personal data hidden>> wrote:
Dear Randall,
Thank you for using Ask Extension. A request for support has been created and a representative will follow-up with you as soon as possible. Questions are usually answered within two business days. You can view this question's progress online.
YOUR QUESTION #0141583:
Oak Tree leaves
Hello, can someone diagnose a problem with my oak tree by viewing a picture of a leaf? The tree is in my front yard, lots of clay in our soil, I have rock around the trunk then my lawn. Picture attached. It’s impacting the lower leaves while the leaves at the top don’t look as bad. In the past couple years I’ve had wasp and aphid problems. This same issue happened last year and the leaves turn brown and dry. Not sure if this is a gamble oak or what, but several neighbors call it scrub oak. Was planted 5 years ago and is about 10-15’ tall. Thank youAsk Extension offers one-to-one expert answers from Cooperative Extension/University staff and volunteers within participating Land-Grant institutions across the United States.
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Yes, you are correct. Did you see my response I sent? I've copied it below. It was sent 6/5.
Hi Randall,
This looks like oak leaf blister, which is a common fungus that the group of white oaks tend to get. Fortunately, it just looks bad, but rarely causes harm to the tree. The oak you have appears to be a bur oak, which is a type of white oak.
Unfortunately, it's too late to do anything, as preventative fungicides are the only option and must be sprayed during budbreak.
Here's more information from Utah State: https://extension.usu.edu/planthealth/ipm/notes_orn/list-treeshrubs/oak-leaf-blister
This fall, rake up the leaves and throw them in the trash. This disease is most common during wet springs, which we didn't really have, but perhaps the temperatures and timing were "just right" this year.
Randall D Howard, CPL
On Jun 10, 2024, at 7:52 PM, Ask Extension <<personal data hidden>> wrote:
