The composite flowers, produced between August and October, have blue to violet rays.

[3] American botanist John Leonard Riddell originally described this species in a publication dated to April 1835 as Aster oolentangiensis[5] after finding it in forests on the Olentangy River near Worthington, Ohio.

[6] The synonym Aster azureus has also been used, but this was not published until November 1835,[note 1] so Riddell's epithet has priority.

It occurs widely in the Midwestern United States and in eastern prairies, from Texas to Minnesota.

The species is typical of higher quality natural areas, especially those with disturbances such as wildfire.