CORRELATING AGRICULTURE IN SOUTHERN STATES. 41 
and 40 pounds potash; and 1 ton of stubble provides 10 pounds nitrogen, 4 pounds 
phosphoric acid, and 20 pounds potash? 
2. A farmer plants an acre to cotton three years in succession, using 400 pounds of 
fertilizer each year. The first year the acre produces a bale, the second year five- 
sixths of a bale, and the third year two-thirds of a bale. What is the income for the 
three years if cotton sells at 12 cents a pound and seed at $20 a ton? (A bale of lint 
weighs 500 pounds. The seed of a bale 800 pounds.) 
3. The same farmer plants another acre, using the same amount of fertilizer each 
year, to cotton the first year and makes a bale, to corn and peas the second year and 
produces 75 bushels of corn and 10 bushels of peas, to oats and peas the third year and 
produces 40 bushels of oats and 15 bushels of peas. Find the value of all the crops 
if corn is worth 75 cents per bushel, cotton the same as in problem 2, peas $1.50 a bushel, 
and oats 50 cents per bushel. 
4. Find the fertilizer value of one-fourth ton of oat stubble and one-half ton pea 
vines turned under during the three years in problem 3. 
5. Find the total values in problems 3 and 4 and compare with 2. 
6. Will the method followed in problem 2 or that in problem 3 furnish more humus? 
Which method will leave the soil in better physical condition? 
MAY. 
1. Field tiling costs about as follows: Three-inch, 3 cents per foot; 4-inch, 4 cents 
per foot; 5-inch, 5 cents per foot; and 6-inch, 6 cents per foot. Find cost of 500 feet 
of each? 
2. A man owns a plat of swamp land 48 rods long and 10 rods wide. Find its area 
in acres. 
3. There is a small stream running through the middle of the plat lengthwise. To 
drain the plat into the stream it requires 4-inch tiling laid 2 feet deep every 4 rods. 
Find cost of tiling to drain the plat. 
4. It costs 12| cents a rod to dig the ditches. What will the ditching cost? 
5. What will the system of drainage cost in 3 and 4? 
6. The plat has been producing 2 tons of hay valued at $10 per ton. How many 
bushels of corn per acre will the plat now have to produce the first year to pay for 
the drainage system and make a return equivalent to the usual income from the hay 
crop? 
7. Fifty insects per day is a low estimate for the average bird to eat. On an 80-acre 
farm there is an average of 2 birds per acre. How many insects will be consumed on 
this farm per day? Per month? 
8. If there averages 1 bird per acre, how many in your State? 
9. If each bird eats one-tenth of an ounce of weed seed per day, how many pounds 
of weed seed would be consumed in the State in a day? In August, September, 
and October? 
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