1 Ocr., 1901.] QUEENSLAND AGRICULTURAL JOURNAL. 375 
subsoil and leaving a large proportion of it on the surface ready for a succeeding 
crop. Notwithstanding the prejudice in favour of farmyard manure, which in 
many cases is difficult, if not impossible, to obtain in sufficient quantity, there 
is no real difficulty in maintaining a farm in good heart by means of artificial 
fertilisersifthese are used judiciously in conjunction with green manuring, com- 
posts, and such stable manure as is procurable. The best way of applying chemical 
fertilisers is in small quantities as helps to the general manures obtained by 
the decomposition of vegetable crops. The crops cultivated on a farm may be 
divided into “nitrogen collectors” and “nitrogen consumers.” The nitrogen 
collectors are peas, vetches, clover, lucerne, &c. These gather their chief supply 
of nitroven from the air,and thereby increase the quantity of nitrogen contained 
in the soil. The nitrogen consumers are cereals, grass, potatoes, turnips, rape, 
flax, &e. As they take next to nothing from the air, they must take it all from 
the soil in the form of nitrogenous salts. 
It follows that it is wasteful to dress leguminous plants with nitrate of 
soda unless the soil is exceedingly poor in nitrogen, which can easily be known 
by the appearance of the plants, and then a small quantity of nitrate is 
beneficial. 
As far as phosphoric acid and potash are concerned, it is unnecessary to 
exactly measure out the quantity required. An intelligent farmer puts an 
excess of these into the ground. But the nitrogen should be measured out as 
exactly as possible. The reason is that as yet we are not able to calculate 
exactly, in the case of a particular crop or soil, the quantities of phosphoric acid 
and potash to be used in order to produce the largest yield, or, what is the 
same thing, to bring into full activity the nitrogenous manure which is to be 
simultaneously applied. Hence the only course is to secure an. excess of both. 
There is no risk of loss, because both these substances are imprisoned by the 
soil ready for later crops if the next following crop has no need of them. It is 
different with nitrogen. Nitrogen is not fastened up by the soil, but remains 
freely movable, and any residue left behind by the crop will be washed down in 
rainy weather and lost. 
Nitrate of soda does not act on the crop while it is in the soil, for no 
sooner is it there than itis promptly taken up by the plant and increases its 
development. Wheat is usually sown on land in good heart, and no special 
application of manure may be necessary beyond a top-dressing of from | to 2 
ewt. of nitrate of soda to be sown as soon as the plants are ready to take it up. 
Jn an ordinary rotation in which barley succeeds a root crop, the phosphate 
and potash required by the cereal will be abundantly present in the soil, and all 
that is required is the application of some nitrogenous manure in sufficient 
quantity (say 250 lb.) to enable the plant to take up its mineral food. 
Oats will give a largely increased yield in response to a much more moderate 
application of nitrate of soda than what is given to a wheat crop. In fact, 
experiment has shown that, with the application of equal quantities of nitrate 
of soda, oats and barley give an average excess in grain and straw double that 
- of wheat and rye. 
As arule, the nitrate should be applied about a week or ten days after the 
_ young plant appears above ground. It will push on the crop through a critical 
period of growth, and enable it to withstand the attacks of grubs and other 
insect pests. As an example, the Scotsman records that a trial was made of 
112 Ib. of nitrate of soda per acre on Black Tartarian oats. Without the 
nitrate, the yield was 36 bushels per acre ; with the nitrate, 64 bushels per acre. 
The oats weighed 41 Ib. per bushel, while the straw on the plot which got the 
nitrate was at least one-third more in bulk. 
The quantity of nitrate to be employed for oats of course depends on the 
nature of the soil and its manurial condition. _ If the soil is comparatively rich 
in nitrogen, a dressing of only from 84 lb. to 1 ewt. per acre should be given, 
and this may be either applied at the time of sowing or harrowed in, or, what is 
preferable in the case of light, porous soils, be simply broadcasted soon after 
