Cyperaceae

Solid, triangular (three-angled) stems without nodes, unlike the round, hollow, jointed stems of true grasses; leaves are arranged in three ranks rather than two, and tiny wind-pollinated flowers hide inside overlapping scales in dense spikelets.

Dominant across wetlands, marshes, and other waterlogged habitats worldwide — the triangular stem alone is often enough to separate this family from grasses at a glance ('sedges have edges').

To check whether a plant belongs to Cyperaceae, compare the leaf arrangement, leaf type, flower symmetry, fruit type, and one distinctive marker together. A single feature can mislead; the family pattern is the combination.