Bullhead lily, also called yellow pond lily, is an aquatic native often founding floating in quiet ponds in the clearings of woods.  Related to waterlilies, it has flat round leaves that float on the water. Flowers are large yellow globes atop a thick, upright stem. This subspecies is distinguished by having red markings in the throat of the flower - which you will probably not be able to observe unless you are sitting in a canoe.