Manual of grasses for North America
Grasses are the world's most important plants. They are the dominant species over large parts of the earth's land surface, a fact that is reflected in the many different words that exist for grasslands, words such as prairie, veldt, palouse, and pampas to mention just a few. As a group, grasses are of major ecological importance, as soil binders and providers of shelter and food for wild animals, both large and small. Some grasses, such as wheat, rice, corn, barley, rye, tef, and sugar cane are major sources of calories for humans and their livestock.