Summer's End is in Sight

The "frog belly" is in full bloom, and a beautiful Eastern Tiger Swallowtail has come to sip the sweet nectar.  I wish I could sip too, and taste this wonderful end of summer banquet. 

There have been dozens of beautiful butterflies on this one group of plants over the last few days.  Wish I had taken more pictures.

As a matter of notice, there have been more butterflies this summer than I can remember in a long time.  Could it be because it has been so very, very dry?