In 1973 Carex cespitosa L., a species new for the Netherlands, was found in the northern part of this country along artificial cut off meanders of the glacial river Hunze. The sedge is closely allied to Carex hudsonii A. Benn., from which it differs mainly by the dark-purple colour of the lowest leafless sheaths, the fresh green colour of the leaves, the small female spikes and the unnerved fruits. A number of details are given regarding the habitat and the distribution of this northern species.