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Three-Square

Schoenoplectus pungens

three square

three-square drawing
three-square side view


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 Three-Square?

Physical Characteristics

Leaves:

  • 2-4 leaves

Scales:

  • Brown in color
  • 0.16-0.2 inches long
  • Well-marked midnerve

Flowers:

  • 28-50 flowers

Spikelets:

  • 1-4 spikelets
  • Immobile
  • 0.28-0.67 inches long
  • 0.16-0.2 inches thick
  • Oval- or sword-shaped

Fruit:

  • One seed
  • Does not open to release seed when ripe
  • 0.09-0.13 inches long
  • 0.08-0.09 inches wide
  • Flat or slightly bulging
  • Smooth
  • Dark brown in color when ripe

Stem:

Rhizomes:

  • Creeping
  • Reddish-brown in color
  • 0.08-0.13 inches thick

Hollow Stems:

  • Growing upward
  • 0.75-5 feet long
  • 0.08-0.23 inches thick

Where Does it Grow?

Three-square can be found in low, moist, often alkaline ground, in water, and around seepage areas.

Pros and Cons of Three-Square

Seeds are consumed by ducks; while geese, muskrats, and nutria consume the rhizomes. 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.

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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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