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Flat Sedge

Cyperus spp.

Flat Sedge Locations in North America
Flat Sedge Locations in Southeast US

fragrant flat sedge
fragrant flat sedge diagram
ricefield flat sedge

ricefield flat sedge diagram
umbrella flat sedge
sharp edge flat sedge

variable flat sedge
variable flat sedge diagram
jointed flat sedge

jointed flat sedge flower
flat sedge

USDA, NRCS. 2018. The PLANTS Database (http://plants.usda.gov, 28 March 2018). National Plant Data Team, Greensboro, NC 27401-4901 USA.
Illustration courtesy of University of Florida/IFAS Center for Aquatic and Invasive Plants. Used with permission.

What is Flat Sedge?

Physical Characteristics

Leaves:

  • Number of leaves vary

Flowers:

  • Grow in dense mass
  • Many spikelets growing in rows

Fruit:

  • Dry
  • Does not open to release seed when ripe
  • Could be round & bulging on both sides
  • Could be 3-angled
  • Typically brown in color

Stem:

  • Hollow stems
  • 3-angled

Where Does it Grow?

Flat sedge can be found in moist places rooted in mud.

Pros and Cons of Flat Sedge

Submerged portions of all aquatic plants provide habitats for many micro and macro invertebrates. These invertebrates in turn are used as food by fish and other wildlife species (e.g. amphibians, reptiles, ducks, etc.). After aquatic plants die, their decomposition by bacteria and fungi provides food (called “detritus”) for many aquatic invertebrates.

What Type of Flat Sedge Do I Have?

There are many types of flat sedge, and they are difficult to identify without using detailed botanical keys. In Texas, there are 61 common species of flat sedge, 8 of which are listed below.  Click on the buttons to learn more about each individual species.

Cyperus articulatus
Cyperus difformis
Cyperus haspan
Cyperus involucratus
Cyperus iria
Cyperus odoratus
Cyperus floribundus
Cyperus pseudovegetus
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Photo Credits: The majority of the aquatic plant line drawings are the copyright of the University of Florida Center for Aquatic Plants (Gainsville). They are used with permission.

Aquatic plant photographs were provided by David Bayne, Jim Davis, Kelly Duffie, Billy Higginbotham, Michael Masser, John Clayton, Chetta Owens, Diane Smith, Joe Snow, Don Steinbach, Bridget Robinson Lassiter and Peter Woods.

You may use these photos, so long as you give credit to AquaPlant.

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