Answer: Spiders prey on other insects rather than on plant parts so I suspect the holes in the leaves are the work of caterpillars or beetles rather than spiders. If so, the spiders have arrived to control the pesty insects and you don't need to do a thing. Black spots on the leaves can indicate a disease, and it's difficult to diagnose without actually seeing the problem. Maples are prone to bacterial leaf spot, fungal leaf spots and tar spots. The control is different for each so why not take a sample of the problem to your local Cooperative Extension office for positive identification and control recommendations? Contact the Extension office at 417-357-6812.
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