THE ROOTS OF PLANTS AND THE SOIL. 11 



plant, and protect it from the too intense action of the 

 sun's rays ; thus aflbrding more time for the extension 

 and developeraent of the roots. The nature of the roots * 

 of rapes, turnips, and tuberous plants, clearly points out 

 the part of the soil from which they draw their chief 

 supply of food. Potatoes are formed in the topmost 

 layer of the soil ; whereas the roots of beets and turnips, 

 sending their ramifications deep into the subsoil, Avill 

 succeed best in a loose soil of great depth. Still, they 

 will also grow well in soil naturally heavy and compact, 

 which has been properly prepared for their reception. 

 Among turnips, the Swedish variety is distinguished by 

 the numerous fibres which the root-stock sends into the 

 ground; and mangelwm'zel, with its strong and rather 

 woody root fibres, is still better suited than Swedes for 

 a heavy clay soil. 



On the lenorth of roots but few observations have been 



o 



made. In some cases it has been found that lucerne will 

 grow roots thirt}^ feet, rape above five feet, clover above 

 six feet, lupine above seven feet in length. 



A proper knowledge of the radication of plants is the 

 groundwork of agriculture ; all the operations which the 

 farmer applies to his land must be adapted to the nature 

 and conditions of the roots of the plants which he wishes 

 to cultivate. On the root he should bestow his whole 

 care ; upon that which grows from it he can no longer 

 exert any influence ; therefore, to secure a favourable 

 result to his labours, he should prepare the ground in a 

 proper manner for the developement and action of the 

 roots. The root is not merely the organ through which 

 the growing plant takes up the incombustible elements of 

 food required for its increase, but it may, in another 



* Whenever the term ' root ' is used in this work, the undorgrouiul 

 organs of plants are meant. 



