THE TILLAiii; OF THi: SOIL 67 



Clover aiiil rv(^ aiv aUo apt to become too liaid 

 anil ilrv if allowed to grow to maturity. Ilerb- 

 ««;»' which (Iocs not d<H'ay quickly wlieu jiiowcd 

 d(»wii may seriously injure the crop t'«)r that 

 •-'•ason (74f/). ]*'<>r the coveriutr <'t' herbap:e, the 

 furrow sliould be broa*! and dee}> ; and if the 

 land is to be surface- tilled shortly after the 

 plowing, care should be taken that the furrow- 

 slice turns down lalher Hat, so as to completely 

 cover the plants, 



I'.*>. [tl) The deeper the plowing, the greater 

 the water-storage reservoir will he, other things 

 being eijual; but the plowing nuiy be so very 

 deep as t<^ bring the unproductive subsoil to the 

 surfa« e, in wliich case the increase of storage 

 capaeity may be overbulance*! by the loss of 

 available fertility. On most soils and for most 

 erops, eight or nin»» inches is a suflicient depth 

 for the plow. Shallow soils are both too dry and 

 too wet. They are too dry, because much of the 

 rai!ifall is lost in surface drainage or by very 

 rapid evaporation. They are too wet after every 

 haitl rain, because the water is held near the 

 surface (TOrt). 



•J4. ((') If i.i hard-pan is near the surface, 

 deep plowing will break it up, although the 

 most permanent remedy nniy be undcr-drainago. 

 In very porous soils, however, it may l»e neces- 

 sary to form a hard-pan in order to prevent 



