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Flat Sedge

Cyperus spp.

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

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?


USDA, NRCS. The PLANTS Database (http://plants.usda.gov). National Plant Data Team, Greensboro, NC 27401-4901 USA.

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
How to Manage This Plant
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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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