On ike Jfod/Jicad'ons of the Four-Course Rotation, ^r. 2()3 
mucli of the wlicat-stabblc as possible in autumn, so as in fac t to 
constitute a winter-fallow, the necessity for bare summer-fallows 
is almost removed. 
Still, on thoroughly heavy soils, there will be cases where a 
field is very foul, or the season adverse, when, unless steam- 
cultivation come to our aid, we must be content to go without 
a crop. 
As regards the white straw-crops in the four-course shift, the 
chief alteration requiring notice is the substitution of wheat for 
a part of the barley or oat crop. And if land be in good condi- 
tion, and prices offer a suflicient inducement, there is no reason 
why wheat should not, at any rate on moderately heavy soils, l)e 
grown after such of the root and green crops as are cleared off" 
early enough to admit of its being sown in good season. 
Mangold wurzel is now almost universally followed by wheat ; 
and out of some hundreds of farms, in various counties, on which 
I have had opportunity for ascertaining the point, I could refer 
to but very few on which the breadth under wheat has not of 
late years considerably exceeded that of barley and oats together.* 
It is very observable that the proportion sown with Avheat has 
extended during the last five or ten years, but, doubtless, present 
prices will somewhat check this tendency. 
Some farmers, and good ones too, take a crop of oats or barley 
after the wheat-crop, thus forming a five-course rotation ; but 
on the class of soils which will best bear this addition to the 
white straw-crops, few farmers will Avish to increase the breadth 
in barley and oats at the expense of that in wheat, which is, to 
a certain extent, the effect of this change, whilst on stock farms 
the loss of green and root-crops will be felt as a disadvantage. 
On land, where barley is apt to become coarse, a better sample 
is obtained by thus sowing it on a wheat etch ; and so important 
is this considered in Hampshire, that it is there not uncommon 
to take the crop of barley immediately after the wheat in the 
four-course rotation, and to follow the clover with the root-crop. 
In the neighbourhood of a town and railway station in Essex, 
where special facilities exist for procuring manure and food, I 
have seen the above five-course rotation carried out with apparent 
* It is very important for us to ascertain to vf-hat extent the wheat-plant, -vrith 
its penetrating root and protracted period of growtli, exhausts the soil more than 
barley. In the case of wheat, Mr. Lawes' experiments indicate a great defect in 
the amount of nitrogen removed in tlie crop, and remaining in the soil after har- 
vest, as compared with that supplied to the soil for the growth of the crop. What 
account can be given of this deficiency, except that these elements have been used 
up by the plant in its long battle with an inclement season, as well as in the pro- 
cesses of flowering and ripening the seed, which are common to both wheat and 
barley ? An experiment, recording the comparative results arising from the alter- 
nation of wheat on the one hand and barley on the other, with a green crop, for a 
series of years on the same land, might do good service to agriculture. — P. H. F. 
