United States, Wisconsin, Polk, Horseshoe Lake. Polk/Barron Counties [Polk Co. - from Lat./Long.]
T34N R15W sec12
Muck bottom in water up to 0.5 meter in depth. Common assoc.: (Brasenia schreberi) watershield, (Nymphaea odorata) white water lily, (Nuphar variegata) spatterdock, (Pontederia cordata) pickerelweed, (Potamogeton zosteriformis) flat-stem pondweed.
A few widely scattered plants were located throughout the lake. A concerted effort could quickly eliminate this exotic invasive from the lakeshore.