Hello!

I was on a walk in my neighborhood this morning, and I saw this peony in a median planter area. The whole planter is filled with peonies, and I was surprised to see the leaves of this peony curl and twist in this manner. I even checked to make sure the leaves belonged to the peony and not some other plant, but they were indeed attached to this peony. Any ideas as to what could be causing this? TIA!