do the dead grass areas seem all brown and dead and matted, with no connecting roots,and you can peel the affected area out like a bad toupee? that would lean it toward grubs. Search the internet for "checking lawn for grubs"......something about peeling away a 1 square foot tile of lawn at root line, and counting the number of grubs. Could your lawn service neighbors have had a grub treatment as part of their annual package? absolutely, but it could also be other things like fungus, etc.

According to Cornell, now is the time to use beneficial nematodes against grubs in the northern climes. Beneficial nematodes are available here. They work by bringing a bacterial disease to the grub population. The disease is harmless to mammals, birds, reptiles, toads, and other higher forms of life but fatal to the grubs and many other insects (fleas and ticks for example). When you apply BN, the soil must be moist and you should water them in heavily. The nematodes move around on a film of water so once the soil dries out, they are stuck.

I'm in SW Pa, and I have seen many small holes where I have perennials planted under my trees, I must say that I haven't seen any plants "Dug up" though, but, I am curious what the holes are for. I am sure my pest that has dug holes in my areas where I have plants, isn't likely the same pest, since the plants haven't been dug up, but, I do wonder what pests would dig a hole near plants but not upheave them, but, will hide out in these holes, I've even heard that Copperhead snakes hide in holes, but, I've never seen a Copperhead her in my my yard, the only one I've ever seen was up in the mountains, at a very good amount of elevation from my home. I do think that the holes are likely from Moles.

Most likely that would be a vole, a field mouse. They will eat anything rather than starve. But many other wild animals will do the same.