156 ILLINOIS STATE DAIRYMEN'S ASSOCIATION 



namely, alfalfa, and I don't think anyone will come to grief on 

 the rock of the grain system. The greatest problem is conserva- 

 tion of manure. 



I want to submit to you some data on the subject, as Dr. 

 Hopkins gave. The Maryland Experiment Station conducted an 

 experiment along this line, exposing 8p tons of manure in an 

 uncovered pile for one year. At the end of one year they took 

 the manure remaining and weighed it, and had 27 tons left. It 

 lost more than two-thirds. Just what loss of the nitrogen would 

 result, I cannot say, but probably not that much, but at least half 

 or a little more. If the data that I compiled in this article is 

 correct, a system which would allow a waste like that would go 

 down hill faster than the grain system. The Canadian Experi- 

 ment Station put out 1,938 pounds of organic matter for four 

 months, and at the end of that time the organic matter was re- 

 duced to 655 pounds, just about two-thirds. Here the nitrogen 

 was reduced from 48 to 27 pounds. Roughly speaking, that 

 was almost half in a period of only four months. 



That is all significant. Our manure is valuable largely for 

 nitrogen. It contains about 10 pounds of nitrogen per ton. Ma- 

 nure contains two pounds of phosphate per ton. In spreading 

 one ton of raw rock phosphate on an acre of ground, you get 

 as much as you would in spreading 125 tons of manure on that 

 acre of ground. So it is not phosphate we are spreading manure 

 for, but nitrogen. 



One more experiment I will cite to you, conducted by the 

 Pennsylvania Experiment Station. Four steers were fed for a 

 period of two months. Two steers were kept on a cement floor, 

 with the manure trampled under their feet. The two others 

 were kept on an earth floor, with the manure in an adjoining 

 covered stall. We would think that would not mean much loss. 

 The animal took out 15 to 25 per cent of the nitrogen fed in the 

 feed, and the percentage recovered in the manure was 84.8% 

 from that on the cement floor. That was a larger percentage 

 than the average results would indicate would be recovered, so 

 the handling was almost perfect. From the two steers on the 



