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Blunt Spikerush (Eleocharis obtusa)

• Family: Sedge (Cyperaceae)
• Flowering: June-October.
• Field Marks: The distinguishing features of this spikerush are the very blunt spikelets up to 1/2 inch long.
• Habitat: Roadside ditches, along streams and rivers, around ponds and lakes.
• Habit: Tufted annual from fibrous roots.
• Stems: Erect, smooth, unbranched, up to 18 inches long.
• Leaves: Reduced to sheaths.
• Flowers: One per scale, with several scales per spikelet, each spikelet ovoid to ellipsoid, rounded or slightly pointed at the tip, up to 1/2 inch long.
• Scales: Ovate to obovate, usually rounded at the tip, brown, 1/16-1/10 inch long.
• Sepals: 0.
• Petals: 0.
• Stamens: 3.
• Pistils: 1; styles 2 or 3; ovary superior.
• Fruits: Achenes yellow to brown, shiny, obovoid, about 1/20 inch long, capped by a small, flat tubercle, subtended by 6 barbed bristles.
• Notes: The achenes are eaten by waterfowl.