278 Report of Expei iments on the Groicth of Barley, 
over 20 years, not given any more produce than the immediately 
adjoining unmanured plot, is a sufficient answer to the objection 
that the admixture of a much smaller quantity of the same de- 
scription of ashes with the artificial manures used on the other 
plots, in any way vitiates the results, or obscures the proper inter- 
pretation of them. 
The average annual produce of barley on the land in question, 
without manure, may be taken at about 21 bushels of grain, and 
12 cwts. of straw. 
It will be of interest to compare the produce of barley without 
manure with that of wheat in the immediately adjoining field. 
Table XXVI. (see next page) illustrates the point ; and for the 
sake of easier comparison, the produce of both crops is given in 
pounds. For wheat the average annual produce is given — for the 
-whole 28 years of the experiments ; for the first 20 years, which 
will, perhaps, best compare with the barley, so far as condition of 
land at the commencement of the series is concerned ; and for the 
last 20 years, which comprise the same period as that of the barley 
results, and will, hence, compare best so far as any influence of 
season is concerned, but which succeeds 8 years of the growth 
of the crop without manure. For the barley, the mean produce 
of the two unmanured plots (1 O and 6-1) is given. 
It is seen that, over a period of 20 years without manure, 
the barley has yielded a greater weight of corn, but less of 
straw, per acre, per annum, than the wheat. This is the case, 
whether the produce of wheat be averaged over the whole 28, 
the first 20, or the last 20 years. The average weight of total pro- 
duce (corn and straw together) is, however, much more nearly the 
same for both crops. It is almost identical when the comparison 
is made with the wheat averaged over the whole 28 years ; it 
is in favour of the wheat when the first 20 years of each crop is 
taken, and in an almost exactly equal degree in favour of the 
barley when both crops are taken over the same period, namely, 
the 20 years — 1852-'71, which, in the case of the wheat, suc- 
ceeded the removal of eight previous unmanured crops, but in 
that of the barley were the first 20 years of its continuous growth. 
Prior to the commencement of the experiments the previous 
cropping had been as under : — 
Wheat-Field. Barley -Field. 
Turnips (dunged). Turnips (dung and super- 
phosphate) carted off. 
Barley. Barley. 
Peas. Clover. 
Wheat. Wheat. 
Oats. Barley (sulphate ammonia). 
