WHAT AVAILABLE FERTILITY IS. 273 



soil be reduced to its primitive condition when it was with- 

 out any accumulated stores of available plant food. This 

 term "available," perhaps needs a word of explanation, lest 

 it may be misunderstood. 



If a man possesses a sum of money in coin or current 

 funds, it is available for the purpose of trade. He can pur- 

 chase food; clothing; houses; lands; and any other property 

 with it, without any difficulty. If he should invest his' 

 funds in such property that is readily salable, his means are 

 still available; and he can turn his possessions into money 

 again, with ease. But if he spends his money foolishly; 

 buying property which is not desirable; as for instance tracts ; 

 of land far beyond the boundaries of settlement; his means : 

 are used up and are not available; he can neither sell the; 

 property, nor borrow upon it; and if he needs money for his 

 present uses, he will find himself as poor as the ragged va- 

 grant who begs food from door to door. 



Just so in regard to the fertility of the land. The 

 farmer grows crops and takes from the soil a certain 

 quantity of plant food; this plant food was available; 

 and the plants could take what they wanted of it. In time, 

 by an exhaustive process of culture, all this ready formed 

 soluble matter is used up; spent; and gone; and the soil is 

 left, still containing thousands of pounds of the same kind 

 of matter, but it cannot be reached by the plants, because 

 it is not soluble, excepting to a very small extent. All this 

 plant food; the nitrogen of the atmosphere and of inert or- 

 ganic substance in the soil; and the various mineral matter 

 of the soil; all these are in existence, but are not available 

 and the plants starve upon the soil with all this unavaila- 

 ble food in it. 



For the profitable culture of farm crops, therefore, the 

 farmer must see to it that the fertility of the soil is kept in 

 nn available condition; that as it is drawn upon by the 

 crops, it is replaced by the application of manure; and that 

 fresh supplies are brought forth from the soil by thorough 

 tillage with the most effective implements. 



