146 THE PRINCIPLiES OF AGRICULTURE 



studied. That is, it is not enough that the 

 land be well prepared: it should have the kind 

 of preparation which is demanded by the crop. 



2. The Demands of the Plant 



244. The preparation of the seed-bed differs 

 with the way in which the plant is propagated. 

 Some plants are propagated by a piece or 

 part of an underground stem or tuber, as the 

 potato ; others by a branch of the aerial 

 part, as the willow or sugar-cane. In all of 

 these cases, the buds or eyes are surrounded 

 with food for immediate use. This stored food 

 gives them power to send out strong shoots and 

 to grow for some time without having to secure 

 nourishment from the soil. But many plants are 

 propagated by tiny seeds. These start in 

 life with little stored food, and, therefore, must 

 quickly secure nourishment from the soil ; and 

 the land must, therefore, be very well prepared. 

 These seeds should be planted near the surface, 

 for there will not be strength enough in the 

 infant plant to push its way through, if planted 

 as deep as the potato. 



245. Plants may change or modify their 

 characteristics to adapt themselves to changed 

 conditions. The common red clover is a tap- 

 rooted plant, but if it grows on soil which is 



