Question
QUESTION: I have a white oak in the yard that in the past 2 weeks has been getting small spots on the leaves (several areas per leaf, damage is under the top layer of the leaf, color so far is just pale green/clearer green).  In looking at internet pics, it seems I may have Oak Leaf miners.  What can I do?  Internet sites have said that natural predators help, but I can't find anything that says what the natural predators are...do you know?

Thanks!

ANSWER: Leaf miners will make little trails that start out small in width and then get larger as the larvae of the fly feeds.  The trails will look sort of like a winding path and each one will be different.  If the small patches are circular and are sort of a blister or bump, then I would say the tree had oak leaf blister, a fungal disease that is of no consequence and no control is recommended.  As for the leaf miners, biological or natural control will not owrk in the open environment.  That is for enclosed places like greenhouses.  Chemical control of leaf miners is also difficult because you have to target sprays when the adult lays the egg and before the larvae enter the leaf.  Leaf miners generally do not cause significant damage to plants, just make them look bad.  Please respond back with your observations of which of these problems you think the tree has and I will recommend some procedures to minimize their impact on your trees.  Thanks.

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QUESTION: The small patches are circular blister/bump-like...no winding trails...so it's the case of the oak leaf blister.
I think I read somewhere that you should cut off the infected branches and burn them...any truth to that?
Is there anything we can do to minimize the spread/damage to the tree?  Is there anything we can do to prevent it next year?  
It is just a fungus that floats around -- or is it something I somehow caused??
Thanks so much for your help!!!

Answer
There is no need to try to control oak leaf blister.  It will not harm your tree.  It will be heavy in some years and almost non-existent in others.  You can rake up fallen leaves in the fall and burn them.  There is no need to cut branches off the tree.  There is no need to try to spray a fungicide either.  The fungus is airborne and will be around all the time.  It is a very common disease that poses no problem.