Gardening and Horticulture - Japanese Maple Problem

I have a japanese maple that has been at our house since we bought it 2 years ago. It was well established then so it must be at least 5-6 years old. It had mulch around the base however last spring we dug up the mulch because our neighbors 30 some cats were using it as a private bathroom. We did not replace the mulch and were letting the grass grow. Now this summer after the leaves bloomed we notice many of the branches in the middle of the tree do not have leaves on them. What do you think is wrong and how can we fix it. We are in Maryland and so far rain fall has been great and my husband did fertilize the lawn with human waste material. Thanks.

I would replace the mulch in order to keep the moistue levels more steady. Cat waste won't hurt the tree. The new grass will compete with the tree for nutrients.

Japanese maples seem to have strange leaf problems. Mine will have some bare branches from time to time, other times the leaves appear to be burned on the tips. I just keep it watered and feed it in December. It seems to do fine. Mine has been in the ground for five years here.