Hordeum pusillum

Hordeum pusillum
File:Hordeum pusillum (7495179082).jpg
Scientific classification
Kingdom:	Plantae
(unranked):	Angiosperms
(unranked):	Monocots
(unranked):	Commelinids
Order:	Poales
Family:	Poaceae
Genus:	Hordeum
Species:	H. pusillum
Binomial name
Hordeum pusillum Nutt. (1818)

Hordeum pusillum, the little barley, is a diploid annual grass native to the United States (except the westernmost parts), which arrived via multiple long-distance dispersals of a southern South American species of Hordeum about one million years ago. Its closest relatives are therefore not the other North American taxa like meadow barley (H. brachyantherum) or foxtail barley (squirreltail grass, H. jubatum), but rather Hordeum species of the pampas of central Argentina and Uruguay. It is less closely related to the Old World domesticated barley, from which it diverged about 12 million years ago.

Description

The tiny seeds are edible, and this plant was part of the Eastern Agricultural Complex of cultivated plants used in Pre-Columbian times by Native Americans. Before being displaced by maize agriculture, little barley may have been domesticated. Today it can be found in grassland, Sonoran desert, at the edges of marshes, as well as ruderal habitats like roadsides.