608 
Rotation of Crops. 
in every case higher after fallow, with its supposed accumulation, 
than after the leguminous crops, which removed much more 
nitrogen than the succeeding wheat would require. On the other 
hand, on the mixed manure plots, where the condition of the land, 
and especially its nitrogenous condition, was not exhausted, but 
fairly maintained, there was even rather more average produce 
of wheat after the removal of the highly nitrogenous leguminous 
crops than after the accumulations of the fallow. 
It is unsafe to form general conclusions from the results of 
individual years, since the characters of the seasons may have 
so much influence. But it may be observed that, after the 
heavy crops of clover on the superphosphate plots in 1882, and 
more where the roots were fed than where they had been re- 
moved, the wheat crops of the next year, 1883, which were 
higher than average, were lower after the leguminous crop than 
after fallow; whilst, on the highly manured plot, they were much 
the higher after the leguminous crop. In the tenth course, 
however, after the use of potash as well as superphosphate, 
there were fair but by no means such heavy crops of clover as 
in the very favourable season of the preceding course, and there 
was less where there had then been the larger crop ; and in the 
eleventh course also, there was less total produce of beans where 
the heavier crop of clover had been grown in the ninth course. 
The result was, that on the average of the last two courses, the 
wheat gave less instead of more total produce after fallow than 
after the leguminous crops ; but more where the roots had been 
fed than where they had been carted ; that is, more where the 
land was the less exhausted. 
The general result is, that where there was not exhaustion, 
but accumulation due to manure and to increased crop residue, 
the growth and removal of the leguminous crops not only gave 
large amounts of nitrogen in the removed crops, whilst the fal- 
low yielded none, but also left more available nitrogen for the 
succeeding wheat than was rendered available (and remained) 
from the resources of the soil after the fallow. In other words, 
not only were the nitrogen and other constituents obtained in 
the leguminous crops an entire gain compared with the result 
of fallow, but, on the average of years, a somewhat ‘larger suc- 
ceeding wheat crop was obtained as well. 
Here, then, is a striking illusti’ation of the advantages of 
the interpolation of leguminous crops instead of fallow with the 
cereals in our rotations ; and it is seen that the benefit may be the 
greater if the land be not abnormally exhausted, as was the case 
on the continuously unmanured, and on the superphosphate plots. 
Although there was thus great difference between the effects, 
