PROBLEMS 227 



46. What is meant by manure? About what is the fertilizing value of a ton 



of average farm manure? Are all manures of equal fertilizing value? 

 Illustrate. 



47. Explain how feeding affects the value of manure. 



48. Of what value is the liquid portion of manure? 



49. What is the three-fold benefit derived through manure applications? 



50. Why is manure such an excellent fertilizer? 



51. Discuss the care of manure. 



52. Which is more economical, light or heavy applications of manure? How 



has this been demonstrated? 



53. Should manure be plowed under for best results? 



54. When is it good practice to apply the manure to the clover field? 



55. Is winter application of manure a good practice? 



56. Tell of the residual effect of manure. 



57. Can manure alone be used in regenerating soils, or to maintain fer- 



tility? Explain. 



58. What is reinforced manure? What are some materials used for this 



purpose? 



59. What is the best reinforcing material for manure? Give a good illustration. 



60. For an outline summary of this .chapter, see table of contents. 



PROBLEMS 



1. A man applied muriate of potash (43 per cent K) to a peat soil at the 

 rate of 100 pounds pier acre and grew 8 tons of silage corn per acre. Can he 

 maintain the potassium supply of that soil if he continuest his method of 

 fertilization for corn production? 



2. A farmer applied a 3-12-4 fertilizer in the drill at the rate of 125 pounds 

 to the acre, and thereby increased his corn crop 10 bushels per acre. Should 

 he continue this practice? 



3. "A" and "B" sell the same general grade of rock phosphate. A offers 

 his for $10 per ton with a guarantee of 13 per cent phosphorus. B sells his 

 for $12, guaranteeing a phosphoric acid content of 28 per cent. Who sells 

 the cheaper fertilizer? 



4. A land owner wishes to compound a fertilizer containing 5.25 per cent 

 phosphorus and 10.5 per cent potassium for his marsh land. In what propor- 

 tions should he mix acid phosphate (7 per cent P) and muriate of potash 

 (42 per cent K)? 



5. Compound a 2-8-3 fertilizer out of sodium nitrate (15 per cent N) 

 acid phosphate (7 per cent P) and muriate of potash (42 per cent K). 



6. A silt loam contains 0.04 per cent phosphorus. Its original content was 

 0.09 per cent. How much acid phosphate (7 per cent P) would be required 

 to raise the phosphorus content of the soil to its original amount? How much 

 rock phosphate (13 per cent P)? (See question 29.) 



7. Determine the approximate, normal prices of the following fertilizers 

 per ton: Sulfate of ammonia (20 per cent N), rock phosphate (30 per cent 

 P 2 O 5 ), acid phosphate (16 per cent PzOs), nitrate of soda (15 per cent N), 

 kainit (14 per cent K 2 0), muriate of potash (52 per cent K 2 O), and sulfate of 

 potash (50 per cent K 2 O). 



8. At 15 cents a pound for nitrogen, 10 cents for phosphorus, and 8 cents 

 for potassium, determine the fertilizing value of sheep manure. Of good 

 nen manure. 



