Northern Prairie Wildlife Research Center
Northeast Wetland Flora
Field Office Guide to Plant Species
Eriophorum spissum Fernald
- Family: Sedge (Cyperaceae)
- Flowering: April-July
- Field Marks: This species differs by having one spikelet per stem and conspicuous white-bordered scales. The stems are also stiffer than in E. vaginatum.
- Habitat: Bogs, fens.
- Habit: Densely tufted perennial with thickened rootstocks but without stolons.
- Stems: Upright, unbranched, stiff, rough at least near the tip, triangular, up to 2 1/4 feet
- Leaves: Mostly near the base of the plant, elongated, triangular in cross-section, rough to
the touch; upper leaves reduced to sheaths.
- Flowers: Several crowded into a solitary spikelet, the spikelet obovoid to nearly spherical,
up to 3/4 inch high; scales obovate to broadly lanceolate, long-pointed at the tip, dark but
with a white border, the lowest 10-15 scales empty.
- Sepals: 0.
- Petals: 0.
- Stamens: 3.
- Pistils: Ovary superior; styles 3-cleft.
- Fruits: Achenes narrowly obovoid, 1/5-1/4 inch long, subtended by many bright white hairs.
- Notes: Gleason and Cronquist do not differentiate this species from E. vaginatum, but do
consider all the individuals in our range the var. spissum. The achenes are eaten by
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