1 86 An American Fruit-Farm 



cool and dry. Heat and moisture break down 

 the cells of such fertilizers, hence the necessity of 

 burying them. Spread over the stuface and left 

 there, they decay more slowly than when plowed 

 in, — as every farmer knows. He also knows that 

 a heavy application of such fertilizer well plowed in 

 produces more effect the second than the first 

 year. Straw — ^the typical fertilizer of this sort — 

 decays as humus and helps keep the earth moist 

 and porous, and in chemical activity. But the 

 tons of such fertilizer become soluble plant-food 

 gradually and in a relatively long period of time. 

 In proof of this one may cite the effect for years 

 of applying barnyard manure to a field. This 

 means that it becomes soluble plant-food slowly. 

 The fertilizers help keep the soil making. Like 

 the miller, you merely keep the hopper full, the 

 grist grinds on and turns out flour. You keep the 

 soil filled with matter which will dissolve and be- 

 come available plant-food. This is all you can do. 

 You yourself cannot effect the chemical change. 

 All you can do is to supply raw material; Nature 

 does the rest. The earth is only a porous crucible 

 in which heat and moisture convert salts, acids, 

 grass, straw, weeds, — ^whatsoever is soluble, — into 

 plant-food. The plant itself is selective. ''Each 

 after its kind'* is the rule. Grapevines, straw- 

 berries, peaches, have each its appetite. The 

 art of fruit-growing is to know this appetite and 

 how to satisfy it. 



Practically, whatever the plant, tree, vine, shrub, 



