Answer: In my experience it is somewhat unusual to have an insect problem on hydrangeas, so for a positive identification of the cause and suggested controls, if any, you might wish to take a sample to your County Extension office. Their telephone number is: 708-584-6166. In any case, to reduce chances of reinfestation next year, it would be a good idea to remove and destroy the spent leaves as they fall this autumn. Good luck with your hydrangeas!
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