FARM MANURES 233 



LABORATORY EXERCISES 



Exercise I. — Study of farm manure. 



In one or more trips through the community the class may study 

 in a practical way the following points regarding farm manure and 

 its utilization. 



1. Enter a horse stable where fresh manure is lying in the stalls. 

 Observe the odor of ammonia. Explain the reason for such an odor 

 and its significance. 



2. Compare horse manure and cattle manure as to weight, struc- 

 tural condition and amount of water. What relation may these 

 characteristics have to fermentation and to the handling of the 

 manures ? 



3. In the same way compare swine, sheep and poultry manures. 



4. Examine the teachings from an exposed manure pile. What 

 is the color of such liquid and what plant-food materials does it prob- 

 ably contain ? 



5. Study the various ways of handling manure that are in vogue 

 in the community. List and discuss their good and poor points, 

 remembering that the method that would entail the least loss of 

 plant-food material may not always be practicable, due to lack of 

 capital or to the press of the season's work. The common ways 

 of handling manure are : hauling directly to the field and either 

 (1) spreading or (2) leaving in piles for later distribution, (3) stor- 

 ing in a covered barnyard, (4) storing in a manure pit, (5) allowing 

 manure to be tramped down behind the animals or (6) storing in 

 piles either under cover or exposed. 



6. Study the mechanism and operation of a manure-spreader. 

 An efficient spreader should run easily and yet distribute the manure 

 evenly and in a finely divided condition. 



Exercise II. — Experiments with farm manure. 



Plat experiments similar to those suggested in Exercise IV, Chap- 

 ter XVI might be carried out with profit with farm manure. The 

 effect of different amounts of manure, the relative returns of manure 

 from different classes of animals, the influence of lime on the return 

 from the application of manure, and the residual influence of manure 

 are only a few of the possible tests that might be made. 



Tests as described in Exercise III, Chapter XI might be carried 

 out with manure as well as with commercial fertilizers and lime if 

 plats of soil are not available. 



