Hi, Dr. Hill,
This wildflower was photographed June 20 in the Piedmont region along a country road in full sun.
this wildflower is Aster solidagineus, the white-topped aster. The name of this, and essentially all of our other asters, have been changed [not by me!], and this species is now known as Sericocarpus linifolius. It is widespread in South Carolina. You can find out more about it here: https://en.wikipedia.org/wiki/Sericocarpus_linifolius
Your images are very, very nice!
I hope this helps.
Steve Hill, Botanist, SCNPS