COST OF GKOWING COEK 67 



10. How many cubic feet of cultivated soil are there 

 in 1 A. if soil is cultivated 4 in. deep ? if soil is cultivated 

 6 in. deep ? 



11. If a cubic foot of soil weighs 75 Ib. and contains 

 3^ oz. of nitrogen, 1 J oz. of phosphoric acid, and 4 oz. of 

 potash, find the number of pounds of each of these ferti- 

 lizing substances in 1 A. of cultivated soil 4 in. deep ; 6 in. 

 deep ; 8 in. deep. Why plow deep ? 



12. How much more plant food is made available by culti- 

 vating the soil 6 in. deep than by cultivating it 4 in. deep ? 



COST OF GROWING CORN ON ROUGH LAND 



74. The farmer should know the cost of growing a bushel 

 of corn on his farm. This will enable him to determine to 

 what extent he should grow corn. 



EXERCISE 



1. Estimate the cost of growing a 15-acre field of corn 

 when (1) a man with a two-horse plow can break 1 A. 

 per day ; (2) a man with a one-horse plow can lay off 8 A. 

 per day ; (3) a man can plant 5 A. per day ; (4) a man with 

 double shovel can cultivate 3 A. per day ; (5) a man can 

 hoe 1 A. per day ; (6) the corn is to be cultivated 3 times ; 

 (7) the corn is to be hoed twice; (8) a man with team 

 and wagon and 2 helpers can gather 3 A. per day ; (9) a 

 man with a team is paid $3 per day and given 2 meals ; 

 (10) a man with a horse is paid $1.50 per day and given 

 2 meals ; (11) a man working alone is paid 750 per day and 

 given 2 meals ; (12) meals for men are reckoned at 150, for 

 horses at 150 ; (13) seed corn costs 300 per acre. 



2. The yield being 25 bu. per acre, what was the cost per 

 bushel to grow corn in problem 1 ? 



