Brown blistered leaves on a paper birch, damage caused by Fenusa pusilla, late spring in northern Minnesota, United States.

Brown blistered leaves on a paper birch, damage caused by Fenusa pusilla, late spring in northern Minnesota, United States.
Photographer: Steven Katovich, USDA Forest Service, Bugwood.orgRights holder: Steven Katovich, USDA Forest Service, Bugwood.org

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