190 
On Rape-dust. 
and if we have any extent of land prepared, it is in few, very few 
cases, that we ought to risk the loss of a seasonable seed-time by 
adopting such a slow process.* 
Let us not forget to observe here, that Dr. Madden does not 
come to our conclusion as to the best manner of applying rape- 
dust. From the fact of its quick decomposition, he says that it 
should not be drilled u ith the seed, as by so doing it will kill it. 
This is true in a limited sense. Rape-dust will kill the seed if 
a larrje quantity be used. By the drill-system, however, we so 
economize the virtue of the dust, that there is no oecasion to use 
a large quantity. f 
* To dibbling and all methods of planting or sowing wheat very thin 
there is one great objection : the wheat is apt to branch too much, the 
consequence of which is an injury to the root by the winds, &c., owing 
to the increased leverage of a number of stems. The same principle 
will account for the fact of wlieat being broken down near the root, or 
' ioad-legged,' the result of which is an uneven ill-fed sample. Another 
evil to fear is, that the free supply of the atmospheric gases, moisture, 
&c., arising from there being so few plants, should stimulate the plant 
to put forth such a luxuriant foliage and such a number of stems that 
the root will not be able to convey the matters essential to the perfect 
nutrition of each branch in the latter stages of its growth (a larger sup- 
ply of nitrogen, be it remembered, is required to perfect the grain tlian 
to maintain the straw), the consequence of which is a large crop of 
straw and a deficiency of grain. The case alluded to by Professor 
Liebig of a vineyard being stimulated to the production of so much 
W'ood that it became in two or three years almost barren — the fact that 
if our fruit-trees be permitted to put forth many branches they will bear 
little fruit — and the case, instanced in a preceding note, of barley being 
stimulated by rape-dust to too great and quick a production of straw — 
are familiar illustrations of the evil to be feared from one root having 
to perform the functions of two or three, and to support, mechanically 
and clicmically, several stems. Even the turnip, when it has too free 
access to the soil and the atmosphere, cannot perfect its bulb. — The 
Author. 
t " Care must be taken," says Dr. Madden, ' Prize Essays, Highland 
Society,' June, 1842, "in the application of this manure, because if 
drilled in with the seed it would inevitably burn it up : when used for 
barley, the dust is sown about eight days before the seed." Now I must 
say that I have seen many thousands of quarters of rape-dust used, but 
never saw an instance where it was sown a week before the seed. In 
fact there is no necessity for it, as we may use with perfect security any 
quantity iqi to three quarters per acre, and this is more than ought to be 
used to any grain crop, because, as the manure does not last, it is as 
much as the crop will pay for. Where even three quarters per acre are 
used once, two quarters, and even one quarter, is used a thousand times, 
at least in this neighbourhood. I may also add that I never saw a case 
in which rapc-dust, when used in the quantity I have mentioned, though 
