Common names: Dollar bonnet.
Location: Clear, soft water to depths of 10 feet.
Description: Leaves float on the water surface; stems are firmly rooted; leaves are oval-shaped, 2 to 5 inches long, green on the top and purple on the underside; a dull-purple flower about 1-inch long blooms in June.
Hints to identify: Leaves are similar to a lily pad's but are smaller and have no slit; flowers are smaller than the water lily's; stem is attached to the center of the leaf; has a clear, jelly-like coating on the stem and the underside of each leaf.
Importance of plant: Provides shade and cover for panfish, largemouth bass, and northern pike; is eaten by waterfowl.
Management strategy: See DNR regulations. Because watershield provides good habitat for fish, be conservative, remove only enough to obtain access. If you must treat the plant with an herbicide, begin in early summer before the jelly-like coating develops on the leaves.