450 



STATE BOAKD OF AGRICULTURE. 



TABLE 2. — THE PHOSPHORUS BALANCE ON A DAIRY FARM WHICH CARRIES 20 



COWS, 10 CATTLE. 20 HOGS AND 5 HORSES. 



Loss in process of digestion and handling 



of maniu-e, 40 per cent 326 . 6 



482.5 



phosphorous returned to soil in 482 . 5 

 manure. 



Total phosphorous returned to soil 546 . 14 

 Total phosphorous lost from farm, 298.06 lbs. 

 Pounds of 16 per cent acid phosphate needed to make good the loss, 4,270. 



It is to be noted if one purchases 7.5 tons of bran, feeds it and con- 

 siders that 40 per cent of the phosplioriis does not return to the soil due 

 to its retention by the animals and losses from the manure, there is a 

 deficit of 298.06 pounds of phosphorus on a 100-acre dairy farm, the 

 conditions being as outlined. There are required 4270 pounds of 16% 

 acid phosphate to replace the annual loss. 



The situation is different on a farm where less stock is fed, less feed 

 purchased and much of the crops produced is sold. Under the conditions 

 outlined there are required annually 6880 pounds of 16 per cent acid 

 phate to meet the losses entailed on a 90-acre farm. 



That tlie system of farming followed, the amount of feed purchased and 

 the care of the manure produced govern the phosphorus balance on a 

 farm is further supported by chemical examinations of representative 



The wr'tf'rs are indebted to Professors Brown and Edwards of the Animal Husbandry De- 

 partment !inf1 Professor Rirtell of the Dairv Dppartment for data regarding the weight, feeding 

 and care of animals, used in compiling tables 2 and 3. 



