Widgeon Grass
Ruppia maritima
Widgeon grass, a type of underwater grass, also known as submerged aquatic vegetation (SAV), grows in the Choptank River in Talbot County, Md., on July 17, 2017. (Photo by Skyler Ballard/Chesapeake Bay Program)
Widgeon grass. (Photo by Steve Droter/Chesapeake Bay Program)
Chris Guy of U.S. Fish and Wildlife Service Chesapeake Bay Office holds the reproductive shoot of widgeon grass, including seeds, in Tilghman Island, Md., on July 20, 2012. (Photo by Steve Droter/Chesapeake Bay Program)
Widgeon grass produces seeds that grow at the ends of stalks. (Maryland Department of Natural Resources)
Widgeon grass has straight, delicate, thread-like leaves that grow alternately along slender branching stems. (tedreese/Flickr)
Widgeon grass has an extensive root system with creeping rhizomes. (USDA Natural Resources Conservation Service)
A volunteer holds widgeon grass while assisting a survey with Chris Guy of the U.S. Fish and Wildlife Service Chesapeake Bay Office in Tilghman Island, Md., on July 20, 2012. (Photo by Steve Droter/Chesapeake Bay Program)
Widgeon grass is a bay grass with delicate, thread-like leaves that grow alternately along slender, branching stems. It ranges from slightly brackish upper and middle Chesapeake Bay rivers to the saltier lower Bay.
Appearance
Widgeon grass has delicate, thread-like leaves with rounded tips and a sheath at the base. Leaves grow alternately along slender, branching stems. The grass grows in two forms: an upright, branched form with flowers that stand several feet tall, and a short, creeping form with leaves at the base of the plant. In late summer, long stalks with clusters of individual black, pointed seeds grow from the base of the leaves. Widgeon grass has an extensive root system with creeping rhizomes that lack tubers.
Predators
Migratory waterfowl feed on widgeon grass.
Reproduction and Life Cycle
Widgeon grass reproduces sexually between late spring and late summer when two flowers, which are enclosed in a sheath at the base of the leaves, emerge and grow on a stalk toward the water’s surface. Pollen floating on the water’s surface fertilizes the flowers, which then produce seeds. It can also reproduce asexually, when new stems grow from the plant’s root and rhizome system.
Did You Know?
- Widgeon grass is also known as ditch grass because it sometimes grows in ditches along road sides and farm fields.
- It can be confused with sago pondweed, slender pondweed and horned pondweed. Widgeon grass can be distinguished by its leaves, which grow alternately along the branches, and its seeds, which grow on individual stalks.
Sources and Additional Information
- Underwater Grasses in Chesapeake Bay & Mid-Atlantic Coastal Waters by Maryland Sea Grant
- Life in the Chesapeake Bay by Alice Jane Lippson and Robert L. Lippson
- Chesapeake Bay: Nature of the Estuary, A Field Guide by Christopher P. White
- Bay Grass Key: Widgeon Grass – Maryland Department of Natural Resources
- Species Inventory: Ruppia maritima – Smithsonian Marine Station at Fort Pierce
- PLANTS Database: Ruppia maritima – USDA Natural Resources Conservation Service
Quick Facts
Species
Native
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Size
Leaves reach 4 inches in length
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Habitat
Grows in a wide range of salinities, from slightly brackish (medium salinity) to salty waters (high salinity). Found in fresh water and non-tidal tributaries. Most common in shallow areas with a sandy bottom, but can also grow in soft, muddy sediments.
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Range
Ranges from the rivers of the upper and middle Chesapeake Bay to the saltier lower Bay. Widgeon grass and eelgrass are the dominant bay grass species in the Virginia portion of the Bay.
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Status
Stable