n
to a nitrogenous manure.

_Rothamsted Experiments on Wheat._

Of experiments carried out on the growth of wheat, those which have now
been in progress for over half a century at Rothamsted are the most
valuable and famous. In these experiments the comparative value of
nitrogen and mineral manures on this crop was strikingly exemplified.
The former gave a most marked increase in the crop, while with the
latter little or no increase was obtained. A combination of nitrogenous
and mineral manures, on the other hand, gave the most striking results.
An explanation of these results may be afforded by the fact that in
ordinary farming an excess of mineral matter, as compared with nitrates,
is returned to the soil in the crop residues and in the straw of the
farmyard manure.

Of nitrogenous manures, nitrate of soda, on the whole, showed better
results than sulphate of ammonia.

_Continuous Growth of Wheat._

The possibility of growing fair crops of wheat year after year for fifty
years on the same land, and that without any manure whatever, is among
the most striking of the results of these famous Rothamsted wheat
experiments.

_Flitcham Experiments._

In conclusion, we may refer to Mr Cooke's Flitcham experiments. These
were carried out for the purpose of ascertaining the most suitable
manure for the wheat crop under different conditions.

It will be sufficient here to give the recommendations made by Mr Cooke
as the practical outcome of these experiments.

He recommends the application of 10 tons of farmyard manure on light or
mixed soils, after rotation seeds, ploughed in in the autumn, with from
1/4 to 1 cwt. of nitrate of soda, sown in the spring. In certain cases
farmyard manure will be sufficient without the nitrate of soda. When
farmyard manure is not available, the most effective and economical
substitute is 4 cwt. per acre of rape-cake, ploughed in in the autumn,
or 1 cwt. of sulphate of ammonia, sown in the spring, with, in either
case, 1 cwt. of nitrate of soda as a spring top-dressing. In addition to
the above, on land in doubtful agricultural condition, or exceptionally
deficient in one or other of these ingredients, Mr Cooke recommends the
addition of 2 cwt. superphosphate, or 1 cwt. muriate of potash, or both
of these manures, ploughed or harrowed in in autumn.

OATS.

Like barley, oats are generally sown in spring, and, like barley, may be
described as a shallow-rooted crop. They require