210 CORN CROPS 



vating more deeply or more frequently than is necessary 

 in order to accomplish this purpose. 



In TableXLVIII are shown results at the New Hamp- 

 shire, Illinois, and Utah stations with deep and shallow 

 tillage. The Illinois ^ results with methods of cultivation 

 may be summarized as follows : — 



TABLE L 



Kind of Cultivation 



Frequent (4 plats) 

 Ordinary (4 plats) 

 Shallow (4 plats) . 

 Deep (4 plats) 



Average Yield 



FOR Five Years 



Bushels per 



Acre 



68.6 

 68.5 

 71.5 

 65.6 



The principal injury of deep cultivation is that roots 

 are destroj'ed. The depth to which the soil can be 

 stirred without injury to roots depends on the soil to some 

 extent. (See page 28.) In humid regions and clay soils, 

 perhaps 2 inches is the hmit ; in loose loam soils in drier 

 regions, the roots are ordinarily 3 inches below the surface ; 

 while with listed corn, the cultivation may often be as 

 deep as 4 inches. The roots are usually shallow next to 

 the plant and deeper midway between rows. 



It is doubtful whether it would be an advantage to give 

 deep culture, even when it could be done without particular 

 harm to the roots, as illustrated with listed corn at the 

 Kansas station. 



Roots of listed corn are deeper than surface planted 

 corn, and there would be little injury from deep culti- 

 vation. 



» 111. Agr. Exp. Sta., Bui. 31 : 356. 



