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by wind and insects. Since these plants depend on the water for support, they are limp and unable to support themselves in an upright position when removed from water.
Submergent water plants are important sources of food and cover for fish and wildlife. Wild celery (Vallisneria americana) is a valuable food source for waterfowl and is often planted on wildlife refuges. Frogbit or American elodea (Elodea canadensis) and Brazilian elodea (Egeria densa) are commonly sold as aquarium plants.
Some Less Desirable Plants Are
Difficult To Eliminate
Certain submergents, such as watermilfoil, can form dense, impenetrable weed beds throughout lakes and ponds, reducing water movement, casing siltation, depleting dissolved oxygen, and changing the whole character of an aquatic ecosystem. If submergents become established in your garden pond and you are not able to adequately remove them through manual techniques, you may have to drain the pond and allow these plants to dry to a powder. These plants spread by fragmentation, and one small fragment can reintroduce the plant into your pond.
This information is from Diana L. Weigmann, formerly with the Virginia Water Rescources Research Center, and Louis A. Helfrich, Fisheries Extension Specialist at Virginia Tech.
Dr. Diane Relf is a horticulture specialist with Virginia Cooperative Extension and is a member of the faculty of Virginia Tech.
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