The upper staminate flower heads are greenish brown, while the lower pistillate ones are a dense cluster of small white flowers. Leaves narrow and nearly flat.
(Photographed - late June)
Large Fruited Burreed ( or Bur-reed)
Large Fruited Burreed ( or Bur-reed)
Sparganium eurycarpum
Bur Reed Family - Sparganiaceae
Aquatic plant with grass-like leaves and a zig-zag stalk with globular heads of separate male and female flowers.
  Pathology Images Inc. 2000 to 2002