Oak Leaf Blister

Ugly Oaks

BYGLers are reporting that four unrelated springtime problems are causing some oaks in Ohio to look pretty ugly. None of these problems cause harm to the overall health of their oak hosts. However, singly or collectively, they certainly affect the tree's aesthetics.
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Authors
Joe Boggs

Blistered Oak Leaves

Oak leaf blister and oak leaf blister mites produce look-a-like symptoms early in the growing season. Light green to greenish-yellow irregularly-shaped bulging "blisters" rise from the upper leaf surface. An accurate diagnosis requires flipping the leaves over to look at the lower leaf surface.
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Authors
Joe Boggs

Oak Leaf Blister Disease

  Oak leaf blister, a fungal disease caused by Taphrina caerulescens, is widespread this year on a range of oak species, both in the white oak and red oak groups. Symptoms include raised, blistered, greenish-yellow spots on upper leaf surfaces and darker, corresponding sunken spots on lower leaf surfaces, though sometimes the raised and sunken aspects may be obscured. Fungal growth can sometimes be seen on undersurfaces of leaves.

 

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Authors
Jim Chatfield

Blistered Oak Leaves

Oak leaf blister is a disease is caused by the fungus, Taphrina caerulescens.  The fungus overwinters in infected buds and twigs.  Leaf infections occur during moist periods in the spring as leaves emerge.  Early symptoms appear as raised, blister-like, light-green to yellowish-green spots on the upper leaf surface matched with deep depressions on the lower leaf surface.  Eventually, the leaf "blisters" become very apparent as they turn dark brown to brownish-black.  The blisters may be evenly distributed across the leaf and are distinct from the angular, vein-based symptoms...

Published on
Authors
Joe Boggs