Very distinctive stout, tufted sedge with flowering stems to 150cm. Drooping flower-spikes to 15cm long, sheathing leaf-like bracts. Can seed prolifically. Flat dark-green leaves, shorter than stems.
Usually found on heavy, damp, clay soils. Shady woodland, stream edges, roadsides. Native but also found as an introduced garden escape or discard. Less frequent in W and central Ireland.