northeastern bulrush

Scirpus ancistrochaetus is a rare species of flowering plant in the sedge family known by the common names barbedbristle bulrush and northeastern bulrush. It is native to the northeastern United States, from New Hampshire south to Virginia. It used to be found in Quebec but it is now thought to be extirpated there. It was also believed to be extirpated from the state of New York, but at least one population has been rediscovered in Steuben County in 2010. It is threatened by the loss and degradation of its wetland habitat. It is a federally listed endangered species.

This bulrush produces clumps of upright or leaning stems from a fibrous rhizome. The stems sometimes have axillary bulblets. The leaves are up to 68 cm long and are only about 1 cm wide. The inflorescences occur at the tips of the stems and sometimes from the uppermost leaf axil on the side of each stem. Each is made up of clusters of spikelets that are oval in shape and up to 0.5 cm long. They are covered in brown scales with green midribs. The flowers emerge from beneath the scales and the plant can be identified by the straight or curving toothed spines on the developing fruit. Germination occurs around March and seedlings grow from the rhizomes in May. Flowering occurs in June and July and the fruits develop in July through September. This bulrush sometimes hybridizes with Scirpus hattorianus.