CHAPTEE I. 



INTRODUCTORY 



The grass crop of the United States is unquestionably 

 its most valuable crop and so it will continue through 

 all time. True, it is assigned the second place in 

 the United States Census Returns of Agricultural Sta- 

 tistics for 1899. Corn is given the first rank but these 

 reports do not take into account the value of the pasture 

 produced by grasses, nor do they include the ameliorat- 

 ing and renovating influence which these exert upon the 

 soil, and, consequently, upon the production of other 

 crops. The influence referred to relates to the mainte- 

 nance of the supply of humus in the soil and the effect 

 which the presence of the same exerts upon aeration, 

 friability, moisture and available fertility. It is at least 

 an open question if the influence, which the grass thus 

 exerts on subsequent production in other crops, is not 

 as valuable in the aggregate in short rotations as the 

 grass crop itself. It is an open question, therefore, as 

 to whether grass in its death does not give to the agri- 

 culturist a return equal to that given during its life. 



So necessary is the grass crop to the maintenance of 

 an equilibrium in cultivated soils, that, in its prolonged 

 absence, it is not possible to maintain the same in cul- 

 tivated soils. Commercial fertilizers may be made to 

 maintain an equilibrium in fertility, but they do not 



