Home Produce, Inipuiis, and Consuinplioa of Wheat. SCO 
number of acres under the crop. \ et, it must be admitted tliat 
there is as great a deficiency of authentic data in regard to this 
point as to that of area. The only returns we possess are for 
Scotland in 1854, 1855, 1856, and 1857, and for Ireland in 
regard to each individual year included within the jieriod of our 
inquiry. For England and Wales, which, taking the average 
of a scries of years, piobably comprise more than 85 per cent, 
of the total area under wheat in the United Kingdom, there 
are no returns whatever. 
The average produce of wheat per acre is estimated by various 
authorities at amounts chiefly ranging from 28 to 32 bushels ; 
some, however, go below 28, and others higher than 32. Per- 
haps tlie most generally assumed average is 30 bushels. As 
already referred to, Mr. Caird* estimated the average yield per 
acre, in 1850, at not more than 26J bushels ; and he concludes 
that, at the present time, it does not exceed 28 bushels. We 
Lave ourselves always doubted the trustworthiness of the more 
sanguine estimates. 
Granting then, that, for England and Wales, comprising 
about 8J tenths of the whole wheat-growing area of the country, 
we have no official data whatever upon which to found an 
estimate of the yield per acre from year to year, the question 
arises — How are we to attempt to form such an estimate ? 
It is freely admitted that the character of the data we have to 
fall back upon is, a prioi'i, anything but satisfactory. Never- 
theless, it is believed that, in the absence of actual records on the 
point, the most reliable estimates available may, with proper 
care and reservation, be founded on the amounts of produce per 
acre obtained from year to year on certain selected plots (as 
already referred to) in the experimental field at Rothamsted, in 
which wheat has now been grown for 25 years in succession, and 
for 17 years with the same condition as to manuring from year 
to year on the respective plots. 
It has already been shown that the fluctuations in the average 
results obtained on the selected plots from year to year, have, in 
the main, remarkably corresponded in general character and 
tlirection with the fluctuations in the yield of the crop over the 
country generally. But in attempting to get an actual figure to 
represent the average produce of the country each year, it is 
obviously essential carefully to consider the characteristics of 
each harvest, both in the experimental wheat- field and over the 
country generally ; and, accordingly, if it should seem desirable, 
to subject the actual experimental results obtained to modification 
or correction, before adopting them as measures of the average 
3 ield of the country. 
* ' Our Daily Food,' &c., p. 12. 
