204 LESSONS IN AGRICULTURE 



Free Bulletins, U. S. Dept. of Agriculture 



Fanners' Bulletins 



No. 46. Irrigation in Humid Climates. 



No. 116. Irrigation in Fruit Growing. 



No. 138. Irrigation in Field and Garden. 



No. 158. How to Build Small Irrigation Ditches. 



Table showing proportions of water in farm crops: 



One bushel of root crops contains about 55 pounds of water. 



One bushel of potatoes contains about 45 pounds of water. 



One bushel of corn (dry, shelled) contains about 5 pounds of 

 water. 



One bushel of wheat contains about 6 pounds of water. 



One bushel of oats contains about 3 pounds of water. 



One ton of dry hay contains about 300 pounds of water. 



One ton of green feed contains from 1,500 to 1,800 pounds of 

 water. 



NOTE. This represents only the water left in the plants and 

 seeds as a part of them. By far the greater amount used by the 

 plant passes off to the air through the pores in the leaves. 



Problems 



1. If rain falls an inch deep on the level, how many 

 cubic inches is that per square foot ? Per square yard ? 

 Per square rod ? How many cubic feet per square rod ? 

 Per acre ? 



2. About how many barrels of water fall on an acre 

 with one inch rainfall? 



3. How many tons will this water weigh? 



4. The total rainfall during the year in West Vir- 

 ginia is about four feet. What does the water weigh 

 that falls during the year on a square yard of ground? 

 On a square rod ? How many tons to the acre ? 



5. Suppose the plants use one-eighth of this, what 

 is the weight of the water used by a square yard of 

 vegetation ? A square rod ? An acre ? 



6. Suppose potatoes contain three-fourths of their 



