Eriophorum

Eriophorum (Cottongrass, Cotton-grass or Cottonsedge) is a genus of about 25 species of flowering plants in the family Cyperaceae, the Sedge family. They are found throughout the temperate Northern Hemisphere in acid bog habitats, being particularly abundant in Arctic tundra regions.

They are herbaceous perennial plants with slender, grass-like leaves. The seed heads are covered in a fluffy mass of cotton which are carried on the wind to aid dispersal. In cold arctic regions these masses of translucent fibres also serve as 'down' - increasing the temperature of the reproductive organs during the arctic summer by trapping solar radiation.