Polymnia uvedalia (also known as Smallanthus uvedalius); Asteraceae (aster family)
Yet another sunflower-type tall plant blooming along the river. I find it interesting for the size and shape of the leaf, which can get to 12 inches long. The plant itself can grow to ten feet, but the flower doesn’t exceed three inches.
Large-flowered leafcup is found from New York (where it’s endangered) and Michigan (where it’s threatened) south through Florida and Texas.