noun
cotton grass; Eriophorum vaginatum subsp. fauriei
A plant with fluffy white seed heads resembling cotton, found in wetlands. The scientific name is Eriophorum vaginatum subsp. fauriei.
尾瀬ヶ原では初夏にワタスゲの白い穂が見られます。
In early summer, you can see the white heads of cotton grass at Oze Marshland.
From 綿 (wata, 'cotton') + 菅 (suge, 'sedge'), referring to the cotton-like seed heads of this sedge species.