No. 7. DEPARTMENT OF AGRICULTURE. 455 



water that remains in the manure may be in, greater amount than 

 the urine that has been ^vashed out. Fermentation and additional 

 leaching during the summer may easily reduce the value to $1UU or 

 less. 



There are two satisfactory methods for handling manure. One 

 of these is to haul an3 spread the fresh manure daiy, or at least two 

 or three times a week. For this work a manure spreader or at least 

 a wagon used for this work only, is very useful and almost necessary. 



The other method is to allow the manure to accumulate in the 

 stall or covered feeding shed while it is constantly tramped by the 

 animals and kept moist by the liquid excrement, sutticient bedding 

 being used to absorb the excess and to keep the stock clean, and 

 then to haul and spread it on the land when conditions permit. It 

 should not be left, however, to dry out and heat and decompose in the 

 stalls or sheds long after the animals have been turned out to pas- 

 ture. 



Every system of farming should be so planned as to be both prof- 

 itable and permanent, which requires that the productive capacity 

 of the land be maintained. We must understand, then, what the soil 

 contains, what materials are required to produce crops, in which 

 parts of the crops these different materials are deposited, so as to 

 know what part of the produce may be sold and what part should 

 be retained on the farm; also what is done with these important 

 plant food materials when the crops are fed to live stock. 



The older prairie and upland timber soils of the states of the 

 Central West are exceedingly rich in potassium, but relatively 

 deficient in both nitrogen and phosphorus. In the worn hill lands 

 nitrogen is usually more deficient than phosphorus, while in the 

 average long cultivated prairie soil phosphorus is more deficient than 

 nitrogen. 



When grain crops are produced, as corn, oats and wheat, about 

 two-thirds of the nitrogen and three-fourths of the phosphorus, but 

 only one-fourth of the potassium required for the crop are stored 

 in the grain or seed; while about one-tiiird of the nitrogen, one-fourth 

 of the jjliosphorus and three-fourths of the potassium are stored 

 in the straw or stalks. 



Thus a large crop of corn (100 bushels to the acre) will contain 

 about 100 pounds of nitrogen in the grain and 48 pounds in the 

 stalks; 17 pounds of phosphorus in the grain and (5 in the stalks; 

 19 pounds of potassium in the grain and 52 in the stalks. Quite 

 similar relations exist between the grain and straw of other crops. 



Now, with these facts in mind it is plain to see that a system of 

 farming in which the grain is sold and only the stalks and straw 

 are kept on the farm and retiirned to the soil carries off in the gi-ain 

 much of the nitrogen and phosphorus, in both of which these soils 

 are mor(» or less deficient, and which should be returned to the land; 

 while the potassium, of wdiich the soil contains an inexlianstible 

 supply, enough in the first seven inches for 100 bushels of corn per 

 acre every year for seventeen centuries, is largely returned in the 

 strav; and stalks. 



It should be remembered that legume crops, as clover, cowpeas 

 and soy beans, are rich in both nitrogen and phosphorus, three and 

 one-half tons of clover hay containing as much phosphorus and 40 

 pounds more nitrogen than 100 bushels of corn. 



