About Sparganium emersum Rehmann
Taxonomy and Nomenclature
Sparganium emersum Rehmann is a species of flowering plant in the cat-tail family, commonly called European bur-reed and unbranched bur-reed.
Distribution
It has a circumboreal distribution, found across the northern latitudes of Eurasia and North America.
Habitat
This is an aquatic plant that grows in shallow water bodies including ponds and streams, and can occasionally grow to become very abundant.
Growth Form and Stem
It is a perennial herb that forms a floating stem reaching up to 2 meters in length.
Leaf Morphology
Its leaves may either be limp and floating, or stiff and erect, extending above the surface of the water.
Leaf Identification Features
The leaves are flat and straplike, and sometimes have a triangular, keeled base; this feature can be used to distinguish it from the similar species Sparganium angustifolium.
Reproductive System
The species is monoecious, meaning each individual plant produces both male and female inflorescences.
Inflorescence Structure
Both types of inflorescence are spherical: the male inflorescence is a ball of stamens, while the female inflorescence is a ball of developing fruits that grows below the male spheres.
