I could choose almost any state in the union for this to be a native of…it grows almost everywhere (sometimes invasively). I am going with Missouri (as changed from Ohio) purely for the reason that I think I can imagine these there, growing along a river. A plant for wetlands, ponds edges, streams, or general swamps, this is a plant not widely used in landscaping circles but perhaps they should be as they are hugely important food source for a variety of water based animals (beavers, porcupines, muskrats, ducks). Additionally there were a big part of the diet of Many Native American People.  The tubers  are said to taste like a cross between potatoes and chestnuts and can be eaten raw or cooked.

From Wikipedia:

Extremely frequent as an emergent plant, broadleaf arrowhead forms dense colonies on very wet soils that become more open as the species mixes with other species of deeper water levels. These colonies forms long bands following the curves of rivers, ponds and lakes, well marked by the dark green color of the leaves. The plant has strong roots and can survive through wide variations of the water level, slow currents and waves. It displays an affinity for high levels of phosphates and hard waters.

1. IMG_8448, 2. Sagittaria latifolia, 3. IMGP2434_1024x72, 4. Sagittaria latifolia