196 THE PRINCIPLES OF 



the Norfolk four- course, consisting in allowing the seeds to 

 lie two years, and taking oats as the fifth or last crop. North 

 country farmers also find that wheat succeeds better after 

 turnips than does barley. This appears to be owing to the 

 fact that barley cannot be grown of the same high quality in 

 the north as it can be brought to in the south. Secondly, 

 that wheat does not thrive well after clover or " lea " in the 

 north, probably owing to the colder climate, which prevents the 

 rapid decay and nitrification of the clover root, and its passage 

 into the condition of plant food. The Northumberland rota- 

 tion reads as follows : Turnips, wheat, seeds, seeds, oats. The 

 advantages of these changes are very great ; first, in securing 

 the benefits already claimed for a preponderance of grazing 

 in a cool and moist climate ; and secondly, in producing in 

 the oat crop a valuable fodder both in the form of corn and 

 straw. By this change it is practicable to let the seeds of 

 clover lie much longer before ploughing them up than when 

 wheat is to be sown. Land for oats may lie unploughed 

 until January or February, giving the occupier the entire 

 benefit of the autumn and winter feed, which is consider- 

 able when a large flock is kept. Besides this, there are 

 subsidiary advantages in the supply of oat straw, which yields 

 better fodder than wheat straw ; and a further advantage is 

 gained in the greater ease and less expense of ploughing the 

 lands in the winter months. 



The four-course rotation may again be altered by increasing 

 the variety of its crops. Turnips may be grown too fre- 

 quently, the consequence being anbury, clubbing, and finger- 

 and-toe. There is no objection to vary the root-crop within 

 its ample limits by substituting, according to the nature 

 of the soil, swedes, rape, kohl rabi, cabbage, kale, or mangel, 

 thus relieving the ground from the rigid system indicated by 

 the formula turnips, barley, clover, and wheat. Wheat or 

 oats may be substituted for barley, according to circumstances 



