Field- Lab 021 rers 6 1 



for instance, is due, not only lo the fineness of the 

 soil, but to the Ion*;: ages of undisturbed animal and 

 vegetable life by which it has been deepened and en- 

 riched. 



Every now and again, perhaps, there has been a 

 prairie fire, laying waste wide tracts of country, but 

 leaving a large supply of most valuable ashes behind ; 

 and of the value of ashes as a manure, the farmers 

 of Flanders have so high an opinion that they say, 

 * He who spends nothing on ashes is sure in the 

 end to pay double.' Season by season, too, leaves 

 have fallen, and annuals have withered and decayed, 

 adding their remains to those of countless former 

 generations. 



No soil is really fertile, whatever the mineral matter 

 composing it, unless it also contain some amount of 

 organic matter — matter derived from organized, living 

 things, whether animal or vegetable. Organic matter 

 alone is not enough to make a fertile soil ; but with 

 less than one-half per cent, of organic matter, no 

 soil can be cultivated to much purpose. Even with 

 this quantity it will not grow corn of any kind 

 successfully, but it will grow wild crops with less ; 

 and these in time add what is required, if they are 

 let alone for many generations. The Black earth of 

 Russia, which is jet black when wet and brown 

 when dry, owes its colour and much of its fertility 

 to the finely divided and well-mixed vegetable matter 

 which it contains, the remains of countless genera- 

 tions of wild plants, which held undisturbed posses- 

 sion there for ages, but have now made way for their 

 betters. 



All soils contain some amount of organic matter, 



