CHAPTER XIV 

 THE GRASSES 



379. What the Grasses Are. In much of the preceding 

 discussion of forage crops, the term "grasses" has been used in 

 the ordinary sense of common farm usage, as including all hay 

 and pasture plants, whether they are true grasses, legumes, 

 or a mixture of both classes of plants. In this and the suc- 

 ceeding chapters, the term will be used in its more limited 

 sense, as referring only to the true grasses, the members of the 

 Gramineae or grass family, excluding from it the legumes, 

 such as clover and alfalfa. The true grasses are among our 

 most common plants. The number of species is very great, 

 especially in tropical countries; several hundred are native 

 to the United States. In temperate regions, the number of 

 individual plants of the grasses is much greater proportion- 

 ally than the number of species, large areas often being cov- 

 ered with a solid mat or turf of one or more species of grass. 

 The grass family is the most important natural group of 

 plants; it includes not only the pasture and meadow plants to 

 which the term is commonly applied, but also the cereals, 

 which supply a very large part of the food of men and ani- 

 mals. Among the more important of the forage grasses in 

 the United States are timothy, Kentucky blue grass, red- 

 top, orchard grass, Bermuda grass, Johnson grass, brome 

 grass, and the native wheat grasses. 



380. General Characters. Most of the grasses are com- 

 paratively short, herbaceous annuals or perennials, though a 

 few, such as the bamboos of the tropical regions, assume 

 shrub or tree forms. The stems are generally hollow; 



