Question
What are the bugs eating the leaves on my Japanese Maple tree?  They are brown with a shell.  Is there anything that I can spray on the tree to get rid of them.  I live in Charleston, SC.  Thank you for your time.

Answer
Sounds like Japanese beetles.   The adult beetles eat the leaves and flowers of over 300 plants by eating the tissue between the veins, a type of feeding called skeletonizing. The larvae, called white grubs, feed on plant roots and organic matter in the soil, especially under turfgrass. This feeding may result in dead patches of turf that can be picked up like a loose carpet.
The adults are a brown to brilliant metallic green, generally oval in outline, 3/8 inch (8 to 11 mm) long and 1/4 inch (5 to 7 mm) wide. The wing covers are a coppery color and the abdomen has a row of five tufts of white hairs on each side that are diagnostic. The adult beetles normally emerge during the last week of June through July. The first beetles out of the ground seek out suitable food plants and begin to feed.

The adults can be controlled by spraying susceptible plants with insecticides. Over-the-counter pesticides available for this include: acephate (Orthene), carbaryl (Sevin), and several pyrethroids - bifenthrin, cyfluthrin, deltamethrin, lambda-cyhalothrin, permethrin, and others. During the heavy adult activity periods, sprays may be needed every 5 to 10 days.
Spray the foliage with the spray.

For large trees or for all season protection use a product called Bayer Advanced Tree and Shrub Insect Control. This is applied to the soil around the tree and the roots will carry it to the foliage and twigs and when the insects feed they are killed. It will take a couple of weeks to get the insecticide to the foliage of larger trees so I would spray and then apply the Bayer product that way you will kill the beetles present and the soil applied insecticide will keep them from coming back. Here is a web link to this product. Check with your local garden type store for this product.
http://www.bayeradvanced.com/tree-shrub-care/products/12-month-tree-shrub-insect