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Brasenia schreberi


Watershield colony
variable watershield in-situ

Habitat: Watershield is found in the floating-leaved plant community. It thrives in soft- water lakes, ponds and slow moving streams, especially those with sediments that are rich in organic matter.

Description: Watershield is a floating-leaved plant with moderately-sized, (4 to 12 cm long, 2 to 6 cm wide), oval to footballshaped leaves. Long, elastic stems (round in cross-section) rise toward the waters surface from buried rhizomes. Stems are often loosely branching, with a single leaf attached (from the middle of its underside) to the end of each branch. The tops of the leaves are leathery and green during the growing season, grading to brilliant yellows, oranges and reds in the fall. The undersides of the leaves are reddish-purple. All submersed portions of the plant, including the undersides of the leaves, are coated with a clear mucilaginous jelly. The flowers are maroon to purple, less than 3 cm wide, and produced on stalks that emerge just above the water surface.

Watershield Range Map
U.S. range map of watershield

U.S. Range: Watershield is native to Maine and New England, and occurs throughout much of the eastern United States and some western states.

Watershield Flower
The flowers are maroon to purple
and emerge above the water's surface

Annual Cycle: Watershield is an aquatic perennial that propagates by creeping rhizomes, seeds, and winter buds (or turions). Flowers are produced in early to mid-summer. Seeds and winter buds are produced in the late summer, and settle to the bottom as the plants decay. Rhizomes, seeds and winter buds sprout new growth as the water begins to warm in the spring.

Value to the Aquatic Community:The leaves of watershield produce shade for aquatic invertebrates and fish. Waterfowl feed upon the leaves, stems, seeds and buds.

Look Alikes: May be confused with European frogbit, yellow floating heart, mermaid weeds, fragrant water lily, little floating heart, and spatterdock. The unnotched, oval leaves with stems attached dead center help to distinguish watershield from all of these look alikes.

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Watershield flower Watershield in-situ Watershield map Watershield illustration

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