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VERTICAL FARMING 



The most effective of all farm tools in breaking up the sur- 

 face soil is the plow, and its use in working up a tight surface 

 soil into a satisfactory condition of tilth must never be over- 

 looked. The effectiveness of the plow has been improved by 

 using modifications that will disturb the soil to greater depths 

 than is possible with an ordinary moldboard plow. The best 



known tool of this type is the 

 narrow subsoil plow that fol- 

 lows along in the freshly 

 turned furrow of the regular 

 plow, deepening the cultiva- 

 tion several inches. Such a 

 plow does not bring the sub- 

 soil to the surface but simply 

 stirs the subsoil. The depth reached is seldom as much as 18 

 inches and is usually not more than 12 to 14 inches. A more 

 improved implement is the new double disc Spaulding Deep 

 Tilling Machine, which combines in one tool both the surface 



COMMON SUBSOILER 



SPAULDING DEEP TILLING MACHINE 



