I have a pin oak tree, about 20 years old, 47" in circumference and about 40 feet tall. I deep root fertilize yearly and as the soil is not quite right for the species I wIll either spray with liquid iron or put ironite in the ground along the drip line to prevent leaf chlorides. I also used Bonide systemic insecticide this year as I observed galls on the branches . I looked at the leaves today and was surprised at the structure of the leaf veins. I checked the Internet for pests/fungi but found nothing
remotely like this. Does anyone have any suggestions?
