Sparganium angustifolium is a species of flowering plant in the cat-tail family known by the common names floating bur-reed[2] and narrowleaf bur-reed.
It is an aquatic plant, growing in water up to 2.5 meters deep.
Its habitat includes acidic, low-nutrient freshwater bodies such as ponds, lakes, slow-moving streams, and ditches.
It can become abundant, practically covering the surface of the water.
It is monoecious, individual plants bearing both male and female inflorescences.