Northern Prairie Wildlife Research Center
Northeast Wetland Flora
Field Office Guide to Plant Species
Eupatorium rotundifolium L.
- Family: Composite (Compositae)
- Flowering: July-September
- Field Marks: This species differs by its sessile, broadly ovate to spherical leaves and its broad, flat-topped inflorescence of white flower heads.
- Habitat: Moist or dry woods and fields.
- Habit: Perennial herb from thickened rootstocks.
- Stems: Upright, unbranched or branched above, slender, soft-hairy, usually glandular-dotted, up to 4 feet tall.
- Leaves: Opposite, simple, broadly ovate to spherical, more or less pointed at the tip, rounded at the sessile base, toothed, hairy and usually rough to the touch on the upper surface, hairy beneath, conspicuously net-veined, 3- to 5-veined from the base, up to 3 inches long.
- Flowers: 5 in a head, with many heads in a broad, flat-topped inflorescence, each head 1/4-1/3 inch high, subtended by slender-pointed tips, consisting only of white disk flowers.
- Sepals: 0.
- Petals: 5, united to form tubular disk flowers.
- Stamens: 5.
- Pistils: Ovary inferior.
- Fruits: Achenes ellipsoid, about 1/8 inch long, subtended by white hairs.
- Notes: This family is Asteraceae according to Gleason and Cronquist.
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