Keats's "La Belle Dame Sans Merci" ends with the sedge withered from the lake and no birds singing — the absence of this waterside plant marking a landscape drained of life, hope, and beauty; A poet might write "the sedge held the riverbank against the current's argument, its roots entangled with clay and the bones of old floods, its leaves cutting the hand that reached for them without apology"; Gerard Manley Hopkins's attentive eye for the particular forms of plants would naturally attend to the sedge's distinctive triangular stem — the feature that distinguishes it from the round-stemmed rushes and flat-bladed grasses — and its architecture of tufted clumps at the water's margin; In poems about wetland habitats, sedge appears as a keystone species — the plant that defines the character of the fen, the marsh, and the riverbank, creating the habitat that shelters birds, insects, and the complex community of wet-ground life; John Clare describes sedge among the plants of the Northamptonshire fens with his characteristic botanical precision, the specific plant anchoring his poetry to the particular landscape he knew and loved and mourned when it was drained; The sedge warbler and the reed bunting — birds that nest in sedge beds — connect the plant to the sounds of summer wetland, the rapid, chattering song of the warbler running through the riverside sedge in a description of both bird and habitat.