Northern Prairie Wildlife Research Center
Western Wetland Flora
Field Office Guide to Plant Species
Aster hesperius Gray
- Family: Composite (Compositae)
- Flowering: August-October
- Field Marks: This Aster is distinguished by its flower heads up to 1 1/4 inches across with white or bluish purple rays, its purple-tipped bracts and its stems with hairiness in lines below the base of each leaf.
- Habitat: Along streams, in wet meadows.
- Habit: Perennial herb with creeping rhizomes.
- Stems: Upright, usually branched, up to 6 feet tall, smooth except for lines of hairs below the base of each leaf.
- Leaves: Alternate, simple, linear-lanceolate, up to 6 inches long, up to 3/4 inch wide, pointed at the tip, tapering to the base, the uppermost usually without teeth, the lowermost usually toothed, rough to the touch, ciliate along the edges.
- Flowers: Many united into heads up to 1 1/4 inches across, each head with 20-35 white or bluish purple ray flowers and several short yellow tubular flowers forming a disk; bracts subtending each head linear, ciliate.
- Sepals: 0.
- Petals: 5, some of them united to form rays, others united to form tubes comprising the central disk.
- Stamens: 5.
- Pistils: Ovary inferior, slightly hairy.
- Fruits: Achenes elongated, slightly hairy, up to 1/24 inch long, with a tuft of white or tawny hairs at the tip.
- Notes: The achenes may be eaten by birds.
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