286 DRY FARMING 



the older plains States between Kansas and Western 

 Canada. 



239A. The Value of Manure. What has been said 

 about the advantages of organic matter in Chapter III 

 and in other places applies in a greater degree to manure. 

 The value of this fertilizer is not chiefly in the food 



Fig. 95. Cereal Test Plots at Beaver Lodge, Grande Prairie District, 

 Northern Alberta. 



material it carries but rather in its physical and biol- 

 ogical effects on the soil. It not only adds some elements 

 of plant food but it improves the structure of the soil, 

 increases its moisture-holding power, lessens the tend- 

 ency to blow and, perhaps most important of all, in- 

 creases the activity and the number of the desirable soil 

 bacteria that perform the important function of making 

 plant food available. 



According to Hopkins* "a ton of fresh-mixed cattle 

 and horse manure contains about 500 pounds of dry 

 matter, 10 pounds of nitrogen, 2 pounds of phosphorus, 

 and 8 pounds of potassium. ... By leaching and fer- 

 mentation the dry matter, nitrogen, and potassium are 

 lost in approximately the same proportion, but the phos- 

 phorus is lost only about half as rapidly, so that one ton 



*In "Soil Fertility and Permanent Agriculture." 



