222 NITROGEN, PHOSPHORUS AND POTASSIUM 



Net Value of the Increases per Ton of Manure Reinforced with Phosphates 



Manure and treatment 



Net value of 

 increases per 



ton of 



manure * 



(Including 



3 crops) 



Yard manure (untreated) f 



Stall manure (untreated) 



Yard manure +40 pounds rock phosphate per ton . 

 Stall manure +40 pounds rock phosphate per ton . . 

 Yard manure +40 pounds acid phosphate per ton. . 

 Stall manure +40 pounds acid phosphate per ton . . 



$2.55 

 3.31 

 3.54 

 4.49 

 4.10 

 4.82 



* Eight tons of manure were applied to the acre once in a three-year rotation of corn, 

 wheat and clover. The yard manure was taken from the open yard, where it had been ex- 

 posed to the weather for 3 or 4 months during the winter. The stall manure was hauled 

 from the stable directly to the field and spread at once in the early part of winter. The 

 fertilizer was dusted over the manure-spreader loads. 



t The cost of the fertilizer was deducted before computing the net values of increases 

 per ton of manure. 



Though farming with livestock is recognized as an excellent 

 way to keep up the fertility, because of the opportunity of returning 

 to the land much of the fertilizing elements, 11 yet it cannot be 

 assumed that because a farmer has stock on his farm he need 

 give no thought whatever to the future of his soil. Manure is 

 often poorly cared for, causing enormous losses annually. It is 

 evident that the farmer who understands the care, reinforcing 

 and proper use of manure will secure far greater returns from his 

 land, and be able to pass his farm on to others in a much better 

 condition, than the man who farms it without livestock or who 

 farms it without any definite plan for maintaining the fertility 

 of the soil. 



Illustration Material for Lessons. Have on hand four-quart samples of 

 the fertilizers important in your section. Include the four classes, also a few 

 miscellaneous samples. 



Demonstrations. Material Needed. Enough unproductive soil to fill 

 8 two-gallon jars; 16 quarts of a light sandy soil; about 3 pounds of green clover 

 finely chopped, or its equivalent in dry clover chaff; 12 two-gallon jars; 3 one- 

 quart Mason jars; some corn and oat seeds; 8 grams each of sodium nitrate, 

 sodium acid phosphate and potassium sulfate; about 2 quarts of fresh horse 

 dung; and a few strips of red litmus paper. 



11 It is commonly believed that when all crops are fed on the farm, and the 

 manure is carefully cared for and hauled to the fields, soil fertility can be 

 maintained indefinitely. This is impossible, because in the feeding transaction 

 unavoidable losses of the fertilizing elements occur particularly of phos- 

 phorus. 



