Q: The leaves on my large water oak have numerous blisters on them. The tree is also dropping lots of leaves. What can I do to help?

A: Your tree has oak leaf blister and you can’t do much about it. This disease is favored by cool, wet springs; in dry years it isn’t a problem. Despite the leaf drop, trees are rarely permanently affected. Get out your leaf rake and clean up!

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OAK LEAF BLISTER    Taphrina caerulescens