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Water Smartweed (Polygonum amphibium)

• Family: Smartweed (Polygonaceae)
• Flowering: June-August.
• Field Marks: Water smartweed has ovoid spikes less than 2 inches long, composed of red or pinkish red flowers. The leaves are usually rounded or heart-shaped at the base.
• Habitat: Marshes, around ponds and lakes.
• Habit: Perennial herb with rhizomes.
• Stems: Erect, branched or unbranched, smooth or hairy, up to 3 feet tall.
• Leaves: Alternate, simple, broadly lanceolate to oblong, pointed or rounded at the tip, usually rounded or heart-shaped at the base, without teeth, smooth or hairy, up to 8 inches long, 1 3/4-4 inches broad, with a sheath sometimes bearing bristles.
• Sepals: Usually 5, red or pinkish red, united at the base.
• Petals: 0.
• Stamens: Usually 8.
• Pistils: Ovary superior.
• Fruits: Achenes pale brown, not shiny, not triangular, 1/10-1/8 inch long.
• Notes: Waterfowl eat the achenes of this plant.