156 BOARD OF AGRICULTURE. [Pub. Doc. 



oriranisins. Subsequent investigations by Deherain and 

 others have shown that the facts noticed were to be explained 

 upon the ground that the straw and manure contained suit- 

 able food for the organisms, for instance, starch, sugar, xylan, 

 araban, etc., and not to any practical extent on account 

 of organisms which they themselves carried to the soil. 

 Deherain, with his characteristic insight and grasp of experi- 

 mental inquiries, soon showed that in the German experi- 

 ments excessive amounts of manure were mixed with the 

 soil, and that where such moderate quantities are applied as 

 is usually customary, outside of special gardening opera- 

 tions, such serious losses would not occur as had been 

 claimed by the Germans, who had worked under abnormal 

 conditions. He has further shown that manure spread upon 

 the fields or distributed in small heaps suffers a rapid loss of 

 ammonia. The first step is shown by him to be an escape 

 of carbon dioxid (carbonic acid gas), which renders pos- 

 sible the escape of the ammonia, such losses not occurring 

 so long as an excess of this compound is present. Less loss 

 would result, then, when manure is firmly compacted than 

 when it is easily permeable by the air. Serious losses of 

 ammonia from liquid manure, when it is kept separate from 

 the solid portions, do not so readily occur. Deherain states 

 that the ideal way to apply the manure is to take it to the 

 field and to spread it at once, then follow with a plough, 

 turning a shallow layer of soil over the manure at once. 

 Little or no loss of ammonia will occur through a thin layer 

 of soil. It seems probable that Deherain has struck the 

 key-note of the problem, though there is much in the way 

 of carrying out, practically, his last suggestion. If one 

 could always have a rain descend upon the manure as soon 

 as it is spread, provided the surface of the ground is in a 

 state to absorb the liquid, the losses of which he speaks 

 would be reduced to a minimum, even if the manure were 

 left on the surface, since the liquid portion held by the solid 

 would be largely washed into the soil, where, as is well 

 known, it is practically safe. The nitrogen of the solid 

 portion cannot so quickly and readily escape. 



These various investigations have shown that one reason 

 for the superiority of rotted over fresh manure lies in the 



