WORKING THE SOIL 149 



proach of the hot hours of midday, the vicious flies 

 sapping the vitality from his faithful team, he has 

 eased up on the work or quit the job. 



In using the tractor for plowing, there are none of 

 these distressing conditions to be taken into considera- 

 tion, nothing to think of but the quality of work done. 

 It is possible to plow deep without thought of the added 

 burden. Deep plowing may or may not be advisable. 

 But where the soil will stand it, deep plowing at 

 the proper time of year, and when done with judg- 

 ment, holds moisture better and provides more plant 

 food. 



The pull power required to plow different soils varies 

 from about three pounds per square inch of furrow for 

 light sand up to twenty pounds per square inch of 

 furrow for gumbo. The draft of a plow is generally 

 figured from clover sod, which averages about seven 

 pounds per square inch. Suppose a plow rig has two 

 14-inch bottoms, and the depth to be plowed is six 

 inches. A cross section of each plow is therefore 14 by 

 6 inches, or 84 square inches. Twice this for two bot- 

 toms is 168 square inches. Since, in sandy soil, the 

 pressure per square inch is three pounds, therefore 168 

 times 3 pounds equals 504 pounds, the draft in sandy 

 soil. 168 times 7 pounds equals 1,176 pounds, the draft 

 in clover sod. 168 times 8 pounds equals 1,344 pounds, 

 the draft in clay sod. 



The success of crop growing depends upon the way 

 the seed-bed is prepared. The final preparation of the 

 seed-bed can never be thoroughly well done unless the 

 ground is properly plowed to begin with. It is not suf- 

 ficient to root the ground over or to crowd it to one side 

 but the plow must really turn the furrow slice in a uni- 

 form, systematic manner and lay it bottom side upper- 



