Eriophorum (cotton-grass): tufted sedges of bogs and tundra

Description and identifying features

Plants in this genus are typically tufted, perennial sedges with narrow, grasslike basal leaves and erect, often triangular stems. Flowers are small and inconspicuous; the most diagnostic feature is the mass of long hairs attached to each fruit (achene). These cottony hairs form the white or pale tufts that give the plants their common name and aid wind dispersal of seeds. Tufts can persist into late season, creating bright patches on otherwise sombre bogs.

Habitat and distribution

Eriophorum species are native throughout much of the Northern Hemisphere, with a strong presence in boreal and subarctic zones. They are especially abundant in Arctic and subarctic regions and are characteristic components of tundra, peat bogs, fens and other waterlogged acidic soils. These environments favour slow decomposition and peat accumulation; Eriophorum often signals persistent wet, nutrient‑poor conditions.

Ecology and interactions

By producing dense stands and aboveground litter, Eriophorum contributes to peat formation and carbon storage in bog landscapes. The cottony seed hairs facilitate wind dispersal and can help seeds settle among moss and litter. Stands provide cover and forage for invertebrates and birds and influence surface hydrology. In some regions changes such as drainage, peat extraction or shifts in climate interact with Eriophorum‑dominated vegetation, affecting carbon balance and habitat structure.

Uses and conservation

Historically, the soft seed hairs were used by local peoples for stuffing, insulation and as tinder or lamp wicks. Today Eriophorum is sometimes used in naturalistic plantings for winter interest and in habitat restoration where peatland species are reintroduced. Conservation status varies by species and region: many populations remain secure in intact peatlands, but habitat loss, altered hydrology and climate change threaten local populations where wetlands are degraded. For authoritative accounts on species status, distribution and identification consult regional floras and specialist resources such as genus treatments, general flowering plant guides, and family overviews at Cyperaceae portals.

• Common species: well‑known examples include Eriophorum angustifolium, Eriophorum vaginatum and Eriophorum scheuchzeri.
• Identification tip: look for cottony seed heads on triangular stems and habitat in peatland or wet tundra.
• Further reading: distribution summaries and regional plant guides are useful—see distribution and ecosystem pages for northern vegetation at distribution summaries, Arctic plant guides and tundra ecosystem resources.