Native Freshwater Plants

Water Shield, a native floating-leaved plant

Water shield, also known as dollar pad or water target, is a native plant found in Washington's lakes and ponds. It goes by the scientific name Brasenia schreberi, named after two botanists (Brasen and Schreber) who collected and described plants in the late 1700's. It is found throughout Washington and other parts of the northwest, and also is common east of the Mississippi River and in other parts of the world.

Water shield has long purplish stems that reach from trailing rhizomes in the sediment to the floating leaves at the surface. These stems are slightly elastic, so that when the water surface becomes wavy the leaves can bob up and down without breaking off. Each of the leaves is up to 6 inches long by 3 inches wide with a green top and dark purple underside. The leaves attach to the stem directly in the middle, giving it a shield-like appearance. During mid summer the small dark purple flowers rise above the water surface an inch or two to bloom and set seed.

The most interesting feature of this plant is the thick coating of gelatinous slime that covers young stems and the underside of young leaves. This dense gel is secreted by special single-celled glandular hairs within the plant. It creates such a slippery surface that it can make grabbing onto the plant very difficult. This usually makes Brasenia a favorite with children (and some adults!).

Water shield is sometimes confused with young leaves of the larger water lilies (either our native yellow water lily or the non-native fragrant (white or pink) water lilies). However, water lilies have a split in the leaf from the edge to where the stem attaches. The leaves of water shield are completely oval, with no split.

Brasenia is usually found in water from 2 - 6 feet deep growing on soft nutrient rich substrate. It prefers soft-water lakes, so is mostly found in Western and Northeastern Washington. It is a valuable plant for fish and wildlife; young fish like to hide among the stems, and waterfowl eat the seeds as well as the vegetation. Humans also have used water shield. Native American groups used the tuberous roots for food, and the Japanese use young leaves and stems in salads. The Japanese also have processed and used the plants gelatinous coating.