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Giant Arrowhead

Sagittaria montevidensis

Non-Native


USDA, NRCS. 2018. The PLANTS Database (http://plants.usda.gov, 28 March 2018). National Plant Data Team, Greensboro, NC 27401-4901 USA.

What is Giant Arrowhead?

Physical Characteristics

  • Only early stages completely submersed

Leaves:

  • Erect-spreading
  • Usually with stout standing leaf stalks
  • Blades widely oval-shaped
  • Shaped like an arrowhead
  • 8+ inches & wide

Flowers:

  • Usually have a ring of stamen
  • Oval-shaped sepals
  • Curves inward
  • About 0.5 inches long
  • Covers most of the fruiting head

Fruit:

  • One seeded
  • Does not open to release seed when ripe
  • Wedge- or oval- shaped
  • Up to 0.09 inches long & 0.02 inches wide

Stem:

  • Straight
  • Up to 5.75 feet tall
  • Simple or occasionally branching
  • Up to 10 whorls
  • Oval- or sword-shaped

Where Does it Grow?


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

Non-Native

Giant arrowhead can be found in swamps, lakes and ponds.

Pros and Cons of Arrowhead

This plant is not native to North America, but has naturalized in much of the United States. While it is not illegal to possess this plant in Texas, it should not be introduced into new water bodies and should be treated with herbicide when present.

How to Manage This Plant
Plant Glossary

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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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