Herbaceous perennial that raises tight spikes of small blue flowers above its glossy, arrowhead-shaped leaves.  It forms emergent gardens in shallow waters of lakes and ponds, often growing together with water lilies and/or arrowheads.  Pickerel fish tend to dwell amongst the plants.

Fruits contain a starchy seed that can be eaten as is or dried.  Young leaves are often eaten by deer and other small mammals.