MANURES. 37 



fact of its mechanical action on the land that is, its 

 effect, from its light, porous nature, in aerating and pul- 

 verizing the soil. Guano, bone dust, or other fine com- 

 mercial fertilizers act only as such, without in any way 

 assisting to improve what may be called the mechanical 

 condition of the soil. 



All experienced cultivators know that the first year 

 that land is broken up from sod, if proper culture has 

 been given by thorough plowing and harrowing (pro- 

 vided the land is drained artificially or naturally, so as to 

 bo free from water and relieve it from "sourness"), the 

 land is in better condition for any crop than land that 

 has been continuously cropped without a rest. The 

 market gardeners in the vicinity of New York are now 

 so well convinced of this that when twenty acres are 

 under cultivation at least five acres are continually kept 

 in grain, clover, or grass, to be broken up successively 

 every second or third year, so as to bring the land into 

 the condition that nothing else but rotted, pulverized sod 

 will accomplish. This is done in cases where land is as 

 valuable as $500 per acre, experience having proved that 

 with one-quarter of the land "resting under grass" 

 more profit can be made than if the whole were under 

 culture. 



When the rotation by placing a portion of the land 

 under grass cannot be done, then it ig absolutely neces- 

 sary to use stable manure, at least to some extent, 

 if the best results are desired, for continuous crop- 

 ping of the soil. "Where concentrated fertilizers only 

 are used, they will not continue to give satisfactory re- 

 sults after the grass roots or other organic matter has 

 passed from the soil, all of which will usually be entirely 

 gone by the third or fourth year after breaking up. I 

 have long held the opinion that the idea of lands having 

 been permanently exhausted by tobacco or other crops is 

 a fallacy. What gives rise to this belief, I think, is the 



