114 



COLD SUBSOILS. 



2}lants do not j^enetrate much beloiv the surface. The 

 cold and damp subsoil is repugnant to them ; when 

 a drought occurs, and they meet the destroyer not 

 only in the parched earth from above, but in the 

 cold water, charged with noxious gases, from be- 

 neath, what choice have they but death ? AVhen a 

 depth of four feet is prepared for the rpots, they 

 cannot suffer to any great extent, as the drought 

 does not penetrate so deep. The following diagram 

 will illustrate this ; (a) represents the surface soil 

 which is deprived of its superfluous moisture by 

 evaporation, and which thereby loses heat which 

 would be genial to the roots of the tree ; (b) rep- 



resents the subsoil, which, although it lays above 

 the surface of the stagnant water, is yet filled 

 with moisture by capillary attraction, and is so cold 

 that it repels the roots ; yet they are obliged to 

 enter it for partial protection from drought. 



The next figure represents the condition of a 



