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Marsh Boltonia (Boltonia asteroides)

• Family: Aster (Asteraceae)
• Flowering: July-October.
• Field Marks: This white-rayed species is distinguished by its completely unwinged stems.
• Habitat: Wet prairies, wet meadows, along streams, roadside ditches, around ponds and lakes, marshes.
• Habit: Perennial herb with slender rhizomes.
• Stems: Erect, branched or unbranched, smooth, up to 7 feet tall.
• Leaves: Alternate, simple, lanceolate, pointed at the tip, tapering to the base, blue-green, smooth, up to 4 inches long, up to 2/3 inch wide.
• Flowers: Many crowded into a head, the outer white and ray-like, the inner tubular, yellow, forming a disk, each head subtended by numerous small, green bracts.
• Sepals: 0.
• Petals: Some white to pale lilac, united to form rays, up to 2/3 inch long, others yellow, united to form a tube.
• Stamens: 5.
• Pistils: Ovary inferior.
• Fruits: Achenes flattened winged, ciliate, about 1/10 inch long, with 2 small awns at the upper end.
• Notes: The small fruits of this species are eaten by waterfowl.