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Curly-top Smartweed

Persicaria lapathifolia (Polygonum lapathifolium)

Curly-top Smartweed Locations in North America
Curly-top Smartweed Locations in Southeast US

USDA, NRCS. 2018. The PLANTS Database (http://plants.usda.gov, 28 March 2018). National Plant Data Team, Greensboro, NC 27401-4901 USA.
Illustration: USDA-NRCS PLANTS Database / USDA NRCS. Wetland flora: Field office illustrated guide to plant species. USDA Natural Resources Conservation Service.

What is Curly-top Smartweed?

Physical Characteristics

Leaves:

  • Sword-shaped
  • 2-12 inches long
  • 0.39-2 inches wide

Flowers:

  • Drooping cluster
  • Densely flowered
  • Pink or white
  • 0.08-0.11 inches long
  • 6 stamen

Fruit:

  • Round
  • Bulging on both sides
  • Rough texture
  • Dark, shining brown or blackish in color
  • 0.08-0.09 inches long

Stem:

  • Up to 5 feet tall
  • Fleshy
  • Swollen above nodes

Where Does it Grow?

Curly-top smartweed can be found in marshes, wet meadows, ponds, lakes and streams.

Pros and Cons of Curly-top Smartweed

Smartweed seeds are heavily consumed by ducks, small birds, and small mammals. 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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