CHAPTER XIV 

 THE GRASSES 



365. 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 succeeding chapters the term will be used in its more 

 limited sense, as referring only to the true grasses, the mem- 

 bers 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 

 proportionally than the number of species, large areas often 

 being covered 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 mead- 

 ow plants to which the term is commonly apphed, but also 

 the cereals, which supply a very large part of the food of 

 men and animals. Among the more important of the forage 

 grasses in the United States are timothy, Kentucky blue 

 grass, redtop, orchard grass, Bermuda grass, Johnson grass, 

 brome grass, and the native wheat grasses. 



366. 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; the 

 nodes, or joints, are always solid. This construction of 

 the stem allows the plant to stand considerable strain from 



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