We had one very mild late frost, John, but nothing close to what we normally experience. We usually get several hard, late freeze/frost events. Plus, I noticed this before that happened.
I'll run out there today and see if the mosquitoes will leave me alone long enough to focus in on a couple of pictures.
One of the areas in question is quite a bit shadier now than it used to be. I wonder if that could be a contributing factor?