The Composition and Use of Fertilizers. 273 



Amount of Application. — In applying stable manure to soils, 

 it may be kept in mind, as a general guide that a ton of good 

 stable manure approximately contains: 



Ten pounds of nitrogen; 



Five pounds of phosphoric acid, and 



Ten pounds of potash. 



From one-half to two-thirds of this plant food should become 

 available during the first season. 



When stable manure is applied alone, five tons an acre may be 

 suggested as the smallest amount to use. The exact amount will 

 vary, of course, with the condition of soil and the kind of crop. 

 Ten tons an acre ought to be sufficient for general farm crops. 

 It is more economical to apply smaller amounts at more fre- 

 quent intervals. The frequent use of light applications of stable 

 manure keeps the soil in a more uniform condition of fertility and 

 the nitrogen is utilized more fully and with less loss. It is not 

 infrequent that farmers apply 20 tons of stable manure to one 

 acre of land. This means 200 pounds of nitrogen, 100 pounds of 

 phosphoric acid and 200 pounds of potash. Very few farm crops 

 can possibly make use of so much plant food in one season. 



Stable Manure Supplemented by Commercial Fertilizers. 

 ■ — It will probably be found true in most cases that the greatest 

 good can be derived from farm manures by supplementing them 

 by commercial fertilizers. "While this is true of most crops, it is 

 particularly true of garden crops where large amounts of plant 

 food are required. To give a roughly approximate idea, we 

 might say that for every ton of stable manure applied it would 

 be veil to use with it from 50 to 100 pounds of acid phosphate 

 and from 25 to 50 pounds of high-grade muriate or sulphate of 

 potash. This is best accomplished in the manner described on 

 page 245. 



Use of Fresh Manure. — The statements below apply to fresh 

 manure containing only small amounts of coarse litter. It ap- 

 pears to be the prevailing belief, both in the theory and practice, 

 that best results are ordinarily secured by applying stable manure 

 to the soil in as fresh condition as possible. Mixed with the soil, 

 fresh manure decomposes readily, having its own constituents 

 made more available as plant food, and, moreover, rendering 

 available some of the insoluble plant food previously in the soil. 

 In this way losses from destructive forms of fermentation, leach- 

 ing, etc., are mainly prevented. 

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