Any of about 100 annual and perennial species of weeds and forage grasses that make up the genus Bromus, in the family Poaceae (Gramineae). Found in temperate and cool climates, bromegrasses have flat, thin leaves and open, spreading, erect or drooping flower clusters. More than 40 species are found in the U.S.; about half are native grasses. Rescue grass (B. catharticus), a forage and pasture grass, and smooth brome (B. inermis), a forage plant and soil binder, are the economically important species. Downy brome or cheatgrass (B. tectorum), ripgut grass (B. diandrus), and foxtail brome (B. rubens) are dangerous to grazing animals; their spines can puncture the animals' eyes, mouths, and intestines, leading to infection and possible death.
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