Oak tree leaves turning brown - Ask Extension
Hi
I'm in Bedford, Tx. I have 4 relatively small Oaks in the front yard. Moved in about a year ago, so I don't have much knowledge of the history of t...
Knowledgebase
Oak tree leaves turning brown #269643
Asked August 12, 2015, 3:27 PM EDT
Hi
I'm in Bedford, Tx. I have 4 relatively small Oaks in the front yard. Moved in about a year ago, so I don't have much knowledge of the history of the home.
One tree in particular (second on the right), has the leaves turning brown in the middle of Summer. It's not a water thing, I don't think. The other 3 trees seem fine and I've been watering consistently.
I've noticed some insect damage on the lower leaves of all 4 trees, but the other 3 seem pretty healthy.
I've attached several pics of the tree, it's neighbors and a close up of a pretty healthy leaf vs a browning leaf.
Any ideas what it could be or how I might treat it?
Many thanks!
Darin
Tarrant County Texas
Expert Response
Darin,
There are many possible reasons for what you are seeing, and I will go through a few of the more likely ones, but first I would like to say that four oak trees will eventually be too many oak trees for your yard. The trees are competing with each other for water, nutrients and sunlight and there will be winners and losers.
I do think that you are keeping the trees and grass hydrated, so simple water stress is not the problem right now. There are two diseases to consider: Oak wilt and bacterial leaf scorch. Oak wilt is the most serious, but your location in Bedford is not an oak wilt center, and oak wilt is a quick killer of red oaks. Here is a link to more information:
http://plantdiseasehandbook.tamu.edu/landscaping/eight-step-program-to-oak-wilt-management/
Bacterial Leaf Scorch is something that is typically seen in late summer. Usually, portions of the tree canopy will look fine, while others show the symptoms, and your tree doesn't really look like that to me. Here is a link to more information about BLS:
http://www.apsnet.org/edcenter/intropp/lessons/prokaryotes/Pages/BacterialLeafScorch.aspx
Another possible cause is that this is a different oak species from your other trees. This happens from time to time because it is hard to tell the species apart when they are young, and sometimes a tree is mislabeled and planted here when it is a species that needs low pH soils. However, your tree and the leaf don't show the typical symptoms of iron deficiency. The leaf tissue would be would be mostly yellow and the tree would look yellow overall. None of the big three, four if you count just water stress, seem quite right to me. A certified arborist might be able to help. http://www.isa-arbor.com/findanarborist/arboristsearch.aspx
Sorry I don't have a better answer for you. I do think that the relatively cool, extremely wet spring followed by a hot , dry summer has been hard on all our trees.
There are many possible reasons for what you are seeing, and I will go through a few of the more likely ones, but first I would like to say that four oak trees will eventually be too many oak trees for your yard. The trees are competing with each other for water, nutrients and sunlight and there will be winners and losers.
I do think that you are keeping the trees and grass hydrated, so simple water stress is not the problem right now. There are two diseases to consider: Oak wilt and bacterial leaf scorch. Oak wilt is the most serious, but your location in Bedford is not an oak wilt center, and oak wilt is a quick killer of red oaks. Here is a link to more information:
http://plantdiseasehandbook.tamu.edu/landscaping/eight-step-program-to-oak-wilt-management/
Bacterial Leaf Scorch is something that is typically seen in late summer. Usually, portions of the tree canopy will look fine, while others show the symptoms, and your tree doesn't really look like that to me. Here is a link to more information about BLS:
http://www.apsnet.org/edcenter/intropp/lessons/prokaryotes/Pages/BacterialLeafScorch.aspx
Another possible cause is that this is a different oak species from your other trees. This happens from time to time because it is hard to tell the species apart when they are young, and sometimes a tree is mislabeled and planted here when it is a species that needs low pH soils. However, your tree and the leaf don't show the typical symptoms of iron deficiency. The leaf tissue would be would be mostly yellow and the tree would look yellow overall. None of the big three, four if you count just water stress, seem quite right to me. A certified arborist might be able to help. http://www.isa-arbor.com/findanarborist/arboristsearch.aspx
Sorry I don't have a better answer for you. I do think that the relatively cool, extremely wet spring followed by a hot , dry summer has been hard on all our trees.
