Klehm's where I purchased many of the peonies and sent them a picture of the plants. The first question they asked made my heart sink. They asked me if our lawn had had any treatment and yes, it had. Never before have we had a professional treat our yard, but this year we decided to try to get a head start on the weeds that we have battled in the past, and of course we wanted a beautiful, green lawn.
The gal at Klehm's believes that it is chemical damage to the plants- most likely caused by drift. She advised that we cut down the foliage and wait until next spring. Unfortunately, it is likely that the peonies will not come back but only time will tell. I'm sad that we won't have beautiful blooms this year and likely next year (though I still have 6 or so that are doing just fine). Also, it's disheartening to think of starting over when these plants had gotten settled and would be that much bigger this year. I totally understand that if this if my biggest disappointment right now that we are doing really well and life is good. But still.
P.S. Obviously, we are reevaluating our need for a chemically enhanced lawn!