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in many cases the value of the aftercrop depends upon the preceding 

 crop. In other words a proper rotation is a necessary antecedent to suc- 

 cessful farming. The cultivation of some crop with extensive root rami- 

 fications, will prepare the soil for the subsequent growth of a cereal. But 

 the farmer should not deceive himself. Every crop takes away a part of 

 the available plant-food and the field has not increased in fertility, but 

 the plant-food has been made more readily effective for the production of 

 a crop. "The physical and chemical condition of the fields has been 

 improved, but the chemical store has been reduced." "All plants," says 

 Liebig, "without exception, exhaust the soil, each of them in its own 

 way, of the conditions f.or their reproduction." 



A field then, which produces more kindly after rotation, is not neces- 

 sarily more fertile, but is in better physical condition. It has already 

 been mentioned, that the mechanical effects of clover upon soils is not 

 the least among its valuable properties. The reaction rendered possible 

 by the penetration into the soil of the long tap roots and the effect of the 

 dense shade upon the land have a tendency to increase the productiveness 

 of the soil. 



Clover, however, is the greatest of all fertilizing plants. Other legu- 

 minous plants as well as clover collect nitrogen from the atmosphere and 

 save it, but clover more rapidly improves the physical condition of the 

 soil. A crop of clover taken from the land, while it abstracts some of 

 the elements needed for plant growth, yet, in increasing the content of 

 nitrogen, it gives back to the soil much more of value than it takes away. 

 Clover has been called "a trap for nitrogen," which it catches and pre- 

 serves for the nourishing of growing crops. Dr. Kedzie says: "Clover 

 hay or sod contains enough phosphoric acid for more than double an 

 average crop, enough nitrogen for more than four average crops and 

 enough potash for six average crops of wheat." 



The analysis of red clover indicates what manures would increase its 

 growth. Sulphate of lime or land plaster, the phosphates, wood and coal 

 ashes, are all excellent top dressings for the clover field. Common stable 

 manure, containing as it does all the elements of a good fertilizer, is suit- 

 able as a top dressing for any pasture or meadow. 



Sulphate of lime is found on limy or sandy soils, to largely increase 

 the growth of clover. When used on a wheat field seeded to clover in 

 early spring, a "catch" of clover will be secured on the thinnest spots and 

 it will grow luxuriantly after such top dressing. The greatest benefits 

 from an application of commercial fertilizers upon wheat are often ob- 

 tained in this way. A gfood stand of clover, however secured, is the best 

 possible preparation of land for a succeeding crop of wheat. And this 

 arises not only from the available nitrogen which a clover crop supplies, 

 but from the thorough subsdiling which is effected by the deep, pene- 

 trating tap-roots of the clover. They often descend to the depth of four 

 feet in search of food, while its broad leaves "absorb carbon from the 

 atmosphere, changing it into solid matter, and causing elements in the 

 soil to assume organic forms, rendering them more available as food for 

 other crops." If the soil be robbed of its fertility, the deficient elements 

 must be added before clover will "take." 



