284 POWER AND THE PLOW 



consumes 43 per cent, of the power spent on the corn crop 

 up to the moment of harvest, and 60 per cent, of the power 

 required to place wheat on the ground in bundles ready for 

 shocking. Even this expenditure of power is not great enough. 

 A summary of opinions from eight experiment stations places 

 the average depth of plowing for corn by the best farmers at 

 from four and three quarters to five and one quarter niches. 

 Almost without exception it is recommended that from one to five 

 inches be added to the depth to secure maximum yields! 



Over twenty-five millions of horses and mules are now kept 

 on farms to four millions in cities. Probably fifteen millions 

 are ordinarily used for farm work. The remainder comprise 

 the colts and breeding stock required to keep up the supply 

 for town and country, the driving horses and the idlers. In 

 the plowing season the young and old, the able and the infirm, 

 must bend to the collar for four weeks of muscle-straining 

 drudgery drudgery that so reduces the animals in weight and 

 vitality that even the long period of light work and idleness 

 preceding the harvest scarce enables them to recover their 

 condition. And yet, with all this toil there comes from the 

 West the plea for deeper plowing to establish a moisture re- 

 servoir; from the corn belt and the South for a deeper and more 

 mellow feeding area for plant roots. To supply these condi- 

 tions requires power power that cannot be economically 

 supplied by animals because of the high cost of maintenance 

 and the lack of work during all but a few weeks each year. 

 To double the depth of plowing means keeping nearly seven 

 horses for the twenty to thirty days of plowing to each one 

 required at any other time save the brief harvest. 



In the easiest plowing, five or six horsepower-hours are 

 consumed in plowing an acre. Ten, twenty, even forty, horse- 

 power-hours must be applied to more difficult soils for the same 

 result. In addition, the mere effort of a man and two horses in 

 walking over the ground consumes seven million foot-pounds 

 of energy to the acre on the best of footing. Ten horsepower- 



