258 



VAKIOUS HAYS EOT AT ION 



Velvet bean, Mucuna utilis. 



Maple pea, Pisum arvensis. 



Tall fescue, Festuca elatior. 



Burnet, Sangidsorba minor. 



Sheep's parsley, Petroselinum sativum. 



"Vetches, Viciavillosa. 



Lupines, blue, Lupinus hirsutus. 



Lupines, white, Lupinus albus. 



ROTATION OF CROPS. In freshly opened-up country, the first 

 'settlers sometimes grow the same crop year after year. But such a 

 practice is never successful for long, and in all countries where farming 

 has become established, the practice of rotation has become general. 

 The advantages of a rotation are partly convenience in carrying on the 

 work of the farm by distributing the labour of ploughing, drilling, hoeing 

 rand harvesting over a considerable portion of the year, partly the 

 -variety of crops that can be grown and partly, perhaps mainly, ad- 

 vantages which concern the supply of plant-food from the soil. It is 

 chiefly to these last points that consideration will be given here. 



Some crops depend almost entirely upon the surface soil for their 

 nourishment, while others are deep-rooted and find the major portion 

 of their food in the sub-soil. By alternating such crops the wiiole of 

 the soil can be laid under contribution for supplies of plant food. 

 Examples of shallow-rooted crops are seen in the grasses, barley and 

 oats, potatoes and turnips, while mangolds, beets, red clover, lucerne, 

 wheat and rye penetrate far lower in the soil. 



Then, too, though all crops require the same kind of food from the 

 soil, they require very different quantities, and in some cases an 



