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Marsh Mermaidweed (Proserpinaca palustris)

• Family: Water Milfoil (Haloragidaceae)
• Flowering: June-October.
• Field Marks: This species differs by usually having two kinds of leaves, three sepals, no petals, three stamens, and an inferior ovary.
• Habitat: Swamps, floodplain woods, wet roadside ditches, marshes, sometimes in standing water.
• Habit: Perennial herbs, often rooting at the nodes.
• Stems: Erect or sprawling, smooth, up to 2 feet long.
• Leaves: Alternate, those not in water simple, linear-lanceolate to lanceolate to ovate, toothed, smooth, up to 2 inches long; those submersed in water deeply pinnately divided, smooth.
• Flowers: 1-3 in the axils of the leaves, green.
• Sepals: 3, green, free from each other.
• Petals: 0.
• Stamens: 3.
• Pistils: Ovary inferior.
• Fruits: Nutlets hard, sometimes winged, up to 1/4 inch long, containing 3 seeds.
• Notes: The seeds are eaten by waterfowl.