TILLAGE 21 



worms, are checked by plowing in the fall. The paature 

 insects lay their eggs in the ground in the fall, aad if the 

 eggs are not disturbed, they hatch out the next spring, and 

 it is the young from these eggs that do the, damage. Fall 

 plowing disturbs the eggs and many of them' are, destroyed. 



Plowing Helps to Liberate Plant Food. — We learned 

 in another lesson that plants require food in a soluble form; 

 that is, food in such condition that it will dissolve in water. 

 Plowing assists in making portions of the soil soluble, by 

 pulverizing it, breaking up the soil particles, exposing new 

 surfaces, and allowing the sun, wind and water to act on 

 it more freely than they can act on unplowed land. 



Plowing Covers Manure and Crop Residue. — It is gen- 

 erally regarded as good practice to haul manure directly 

 from the barn to the field before it has rotted, as much 

 of its value is saved in this way. If a rather heavy dressing 

 is applied, it is troublesome in harrowing, sowing and cul- 

 tivating, unless it is plowed under out of reach of the harrow 

 and other tools, but still where the plant roots can reach it. 



The plowing under of manure or vegetable matter saves 

 much of its value from being lost in various ways as it would 

 be if it were left exposed. 

 Questions: 



1. Explain how plowing saves moisture. 



2. In what two ways does plowing destroy weeds? 



3. How does plowing destroy insects? 



4. How does plowing assist in liberating plant food? 

 Arithmetic: 



1. A plow turns a furrow 14 inches wide. How many furrows 

 must one plow to plow a strip 8 rods wide? 



2. How far will a team travel in plowing with a single 14-in. 

 plow a field 8 rods wide and 40 rods long? 



3. How many acres of land in a field 8 rods by 40 rods? 



TIME TO PLOW 



Condition of Soil. — The greatest problem that a plow- 

 man has to solve, is to determine the proper time to plow. 

 Both the season of the year and the condition of the soil 

 must be considered. If a heavy, clayey soil is plowed 

 when it is too wet, the lumps turned up become, when dry, 

 hard clods, which it is very difficult to pulverize into a good 

 seed bed. This is especially true if plowing is done in the 



