Alluvial, limestone woods. Flowers have not opened, and it’s late July (23rd). Note: the last photos are of the tuber from one of the vines. I reburied it afterward. Apios americana has a string of smaller tubers. Apios priceana has a large, single tuber. The species is federally threatened.
So excited to finally find this one! Been keeping an eye out for years. Fairly widespread in one steephead ravine, but absent from adjacent ravines. Easily overlooked as Hydrangea barbara, but much more tapering, lanceolate leaves that are glabrous.
Mushroomhoppers!