Dear sir/madam, I was wondering if you could help me out with my grape tree. This year I noticed that there are bits developing on the leaves and the tree is not growing well. I suspect it has been infested with some sort of pests/bugs. Please enclosed find the photos of the leaves. I would greatly appreciate your assistance in dealing with this issue. Kind regards, Pouya Alaghband
Thank you for contacting Delaware Cooperative Extension. You may receive a short survey with the answer to this question.
Without seeing a physical sample of your grape leaves, it is difficult to tell what the problem is. The raised portions of the leaf remind me of insect galls that are plant responses to the probing of insects or egg-laying of insects. I would suggest turning the leaf over to see what it looks like underneath, or perhaps gently pulling the leaf apart to see if there may be any small insect larvae inside.