FARM AND SCHOOL PROBLEMS. 



Nitrogen Phosphoric Potash 



To find the value of the fertility or fertilizer value removed 

 from an acre, find the production per acre; find the amount of 

 nitrogen, phosphoric acid, and potash removed by referring to 

 the above table and compute the value at the usual price of nitro- 

 gen at 15 c. per pound, phosphoric acid 5 c. and potash 4 c. 



PROBLEMS. 



1. In one year we exported 700 million pounds of linseed meal, 

 and nearly 1,000 million pounds of cotton-seed meal; what was the fer- 

 tilizer value of these two exports for one year, basing calculations on 

 above table? 



2. It has been estimated that there are 5 billion tons of high grade 

 phosphate rocks in the United States. If on an average, a ton of 'phos- 

 phate rock contains 14 per cent phosphoric acid, valued at 5 cents a pound, 

 what is the value of these 5 billion tons as a natural asset to the agri- 

 cultural wealth of the United States? 



3. What is the fertilizer value of one bushel of wheat? Of a 

 bushel of corn? 



4. What was the fertilizer value of the wheat exported fir.m che 

 United States, in 1912, if the amount was 30,000,000 bushels? 



5. What was the fertilizer value of the 40,000,000 bushels of corn 

 exported in 1912? 



6. When a farmer sells a ton of timothy hay, what does he loose 

 in its fertilizer value? 



7. Find the difference between the fertilizer value of a ton of red 

 clover hay and a ton of alfalfa hay. 



8. Which will remove the most of each of the three fertilizers, 

 nitrogen, phosphoric acid and potash from an acre of ground ; 40 bushels 

 of corn or 60 bushels of oats? Find difference in value of fertility re- 

 moved. 



9. Compare the value of fertility removed by 150 bushels of pota- 

 toes with that removed by 20 bushels of soy beans. 



