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Creeping Spikerush (Eleocharis palustris)

• Family: Sedge (Cyperaceae)
• Flowering: June-August.
• Field Marks: This spikerush may be recognized by the presence of rhizomes and its flat achenes with a conspicuous tubercle.
• Habitat: Roadside ditches, along streams and rivers, around ponds and lakes.
• Habit: Perennial herb with creeping rhizomes.
• Stems: Upright, smooth, unbranched, up to 2 feet tall.
• Leaves: Reduced to sheaths.
• Flowers: One per scale, with several scales per spikelet, each spikelet lanceoloid to ovoid, usually pointed at the tip, up to 1 1/2 inches long.
• Scales: Ovate to obovate, usually rounded at the tip, brown, 1/16-1/10 inch long.
• Sepals: 0.
• Petals: 0.
• Stamens: 2 or 3.
• Pistils: 1; styles 2 or 3; ovary superior.
• Fruits: Achenes yellow, not triangular, obovoid, about 1/20 inch long, capped by a small, conspicuous tubercle, subtended by 3-6 barbed bristles.
• Notes: The achenes are eaten by waterfowl.