While looking like a small aster, this short robust plant is actually more akin to goldenrods, being capable of producing hybrids with some of them (but not with any asters). According to the Flora of North America, it occurs in dry, sandy, usually calcareous soil, rock cracks, at rocky outcrops, on limestone pavements, grassy slopes, and in prairies.
Disk florets here are young; the cavity in center is going to disappear, once all florets emerge and open.