NORTH-CAROLINA GEOLOGICAL SURVEY. 143 



other forms of food for cattle will excel them in profit as food. 

 Roots and grain outreach them on this score for special pur- 

 poses at least, though cultivated at a much' greater expense 

 than the grasses. But as nature demands variety, and as the 

 system must have food large in bulk, the place which grasses 

 occupy cannot be filled by the more concentrated nutrients. 

 Disease would follow if cattle were fed exclusively upon 

 grains. 



106. The valuable grasses belong to several genera, in 

 each of which there are several species. 



Although grasses form one-fifth part of the flora of a coun- 

 try, still the number which are cultivated or domesticated is 

 comparatively very small, cattle consume and fatten upon 

 plants which are not grasses, the most important of these be- 

 long to the leguminous plants, the pea family, among which 

 are ranked the clovers. Of these, the red and white clover 

 are the most important. The red clover is a tender plant 

 when young, and difficult to cultivate in a hot dry climate, as 

 many planters have experienced in the eastern part of the 

 State. 



Grasses or Graminge, are subdivided into two great natural 

 orders, which are known under the names of Cyperacem and 

 G-raminacece. In the former, the flowers are monecious or 

 perfect, consisting of imbricated solitary bracts. They com- 

 prehend the coarse swamp grasses, but few of which are es- 

 teemed for fodder or food for cattle. They are, however, 

 eaten in the spring when young and tender. The latter, have 

 usually perfect flowers, sometimes monoecious or polygamous. 

 The external envelopes are called glumes as already stated. 



The southern genera comprehended in the family of the 

 true grasses, are as follows : 



Zizania, Rottboellia, 



Leersia, Cenchrus, 



Oryza, Setaria, 



Mulenbergia, Tripsacum, 



Agrostis, Zea, 



Aristida, Festuca, 



China, Danthonia, 



