Sky Blue Aster

Aster azureus contributes to the ineffable beauty of September and October days when flat-bottomed clouds line up across the brilliant blue sky. 

 Photographed at Ober Savanna Nature Preserve in Starke County, Indiana.

The lovely and descriptive name Aster azureus (Aster = starry), (azureus = sky-blue) has been dropped and replaced, alas!