Prionus Tile Beetle

Recently, while we were working in the vineyard, my husband came to where I was and said, that I need to see this HUGE black beetle. Sure enough, we went back to where my husband had been working and saw this HUGE beetle. Pictures usually don't convey sizes very well, and fortunately, there was a Japanese beetle on a nearby weed and my husband coaxed the weed over to the black beetle so that there was a good reference for the size of this huge, black beetle and I clicked away.

Then we tortured the beetle by turning the grass that the beetle was on so that we could photograph the underside of the beetle. It clung on tightly and we got the shot. Since we didn't know at that time if this was a good beetle or a "bad" beetle, we let it be. Anything this huge is cool, if nothing else and in my humble opinion, should live.
When we got home, we looked on the Internet to see if we could identify this beetle. I entered "huge black beetle with serrated antennae" and got several hits for "Prionus", but since I wasn't sure, I emailed Pamm Cooper at the University of Connecticut Extension Center and she responded that it was indeed a Prionus Tile Beetle. The tile beetle can be brown or black, so we took a picture of the black variety. Information on Bug Guide stated that the female lays 100-200 eggs around the base of various trees, vines, herbs. These include oak, grape, pear, and maize. The larval stage lasts three years or more where they feed on bark and roots.
Well, that is bad news. The other bad news in this photo is that the Japanese beetles have begun to make their appearance. So far, they haven't been the scourge that they have been in previous years.