Northern Prairie Wildlife Research Center
Western Wetland Flora
Field Office Guide to Plant Species
Seep Spring Arnica
Arnica longifolia D.C. Eat.
- Family: Composite (Compositae)
- Flowering: July-August
- Field Marks: This Arnica is distinguished by its 5-7 pairs of sessile, toothless leaves on the stem.
- Habitat: Around springs, along rivers, wet places in woods.
- Habit: Perennial herb with a thickened rootstock and often short rhizomes.
- Stems: Up to 2 feet tall, sparsely hairy, some of the stems often not bearing flower heads.
- Leaves: Opposite, simple, 5-7 pairs per stem, lanceolate to narrowly elliptic, up to 4 inches long, pointed at the tip, tapering to the sessile or somewhat clasping base, sparsely hairy, usually without teeth.
- Flowers: Borne in heads 1-2 inches across, each head consisting of 8-13 yellow ray flowers and several yellow disk flowers; bracts subtending each head long-pointed at the tip,
- Sepals: 0.
- Petals: 5, some united to form yellow rays, others united to form short yellow tubes that comprise the disk.
- Stamens: 5.
- Pistils: Ovary inferior, smooth or hairy.
- Fruits: Achenes elongated, smooth or hairy, with a tuft of tawny hairs at the tip.
- Notes: The achenes may be eaten by birds.
Previous Species -- Mountain Arnica (Arnica latifolia)
Return to Species List -- Group 7
Next Species -- Hairy Arnica (Arnica mollis)