bulrush

An aquatic, rush-like perennial (Scirpus lacustris), found almost everywhere; stems to 3 m/10 ft; leaves in tufts; flowers tiny, perianth reduced to six rough bristles, in oval, brown spikelets. The name is sometimes misapplied to reedmace. (Family: Cyperaceae.)

The term bulrush (or sometimes as bullrush) typically refers to tall, herbaceous plants that grow in wetlands. However, as a common name for a plant, bulrush can mean very different things in different parts of the world.

In British English, bulrush is sometimes incorrectly the common name for Typha, called "cattail" in American English.

http://www.countrysideinfo.co.uk/wetland_survey/reedmace.htm

In American English, a bulrush is any one of several plants in the family Cyperaceae, typically of the genus Scirpus, Bolboschoenus, or Schoenoplectus. Rushes are similar plants classified in the family Juncaceae In the Book of Exodus in the Bible, the infant Moses was found in a basket made of bulrushes, a reference to Cyperus papyrus.