“Well, I’ve figured a good deal on manure,” was the reply, “and I think with four fields producing such crops as you counted on, that I could possibly put ten or twelve tons to the acre on one field every year.”

“That would return from 100 to 120 pounds of nitrogen;” said Percy, “instead of the 173 pounds possible to be returned if there is no loss.  There are three methods that may be used to reduce the loss of manure:  One of these is to do the feeding on the fields.  Another is to haul the manure from the stable every day or two and spread it on the land.  The third is to allow the manure to accumulate in deep stalls for several weeks, using plenty of bedding to absorb the liquid and keep the animals clean, and then haul and spread it when convenient.”

“I’m afraid that last method would not do at all for the dairy farmer,” said Mr. Thornton.  “You see we have to keep things very clean and in sanitary condition.”

“Most often the cleanest and most sanitary method the average farmer has of handling the manure in dairying,” said Percy, “is to keep it buried as much as possible under plenty of clean bedding; and one of the worst methods is to overhaul it every day by ‘cleaning’ the stable, unless you could have concrete floors throughout, and flush them well once or twice a day, thus losing a considerable part of the valuable excrement.  If you allow the manure to accumulate for several weeks at a time, it is best to have sufficient room in the stable or shed so that the cows need not be tied.  If allowed to run loose they will find clean places to lie down even during the night.

“In case of horses, the manure can be kept buried for several weeks if some means are used to prevent the escape of ammonia.  Cattle produce what is called a ‘cold’ manure, while it is called ‘hot’ from horses because it decomposes so readily.  One of the best substances to use for the prevention of loss of ammonia in horse stables is acid phosphate, which has power to unite with ammonia and hold it in a fixed compound.  About one pound of acid phosphate per day for each horse should be sprinkled over the manure.  Of course the phosphorus contained in the acid phosphate has considerable value for its own sake, and care should be taken that you do not lose more phosphorus from the acid phosphate applied than the value of all the ammonia saved by this means.  Porous earth floors may absorb very considerable amounts of liquid from wet manure lying underneath the dry bedding, and the acid phosphate sometimes injures the horses’ feet; so that, as a rule, it is better to clean the horse stables every day and supply phosphorus in raw phosphate at one-fourth of its cost in acid phosphate.”

“Before we leave the nitrogen question,” said Mr. Thornton, “I want to ask if you can suggest how we can get enough of the several million dollars’ worth we have in the air to supply the needs of our crops and build up our land?”