0,7 the Modifications of the Four- Coarse RJii'iirii, S^ c. 259 
is tlie partial substitution of otlier crops in the third year of the 
-course, so as only to repeat the red clover once in eight or even 
sixteen years. 
In many counties it is usual to sow a mixture of Avhite clover 
and trefoil for feeding, with half the spring corn ; and often one 
or two pecks of English or Italian ryegrass are added to increase the 
feed. This addition cannot be recommended ; for, though the 
quantity of keep is considerably increased, it is dearly paid for 
by the damage done, especially by the Italian variety, to the 
succeeding wheat crop ; a fact which I have not only repeatedly 
observed mvself, but Avhich I find to be admitted by larmers in 
almost all parts of the country ; and I believe that the admixture 
of ryegrass is rapidly decreasing in the best-farmed districts.* 
If grown at all, it is far better to sow Italian ryegrass as a dis- 
tinct crop. 
Various reasons are assigned for this failure of Avheat after 
I'yegrass ; but, without discarding all other causes, I think there 
can be no doubt that ryegrass is too nearly allied to the wheat 
plant to be a good preparation for it. 
But even, without ryegrass, we can reckon upon a better crop 
of wheat after mown clover, than after grazed seeds ; and many 
agriculturists consider a better one still after clover twice mown. 
This fact, though generally admitted, is at first sight somewhat 
anomalous ; but it appears to be explained by the large amount 
of roots formed by red clover, when allowed to stand for hay. 
White clover and trefoil would not, of course, under any circum- 
stances, produce so much either feed or root as a good plant of 
red clover ; but keeping the plant constantly fed down from 
spring to autumn, must naturallv check its development under 
ground. If, as has been stated as the result of experiment, the 
weight of roots per acre is more than doubled by letting the 
.clover stand for a second crop, we have an amount of vegetable 
'matter, principally derived from the air, which forms a valuable 
/Iressing for the following crop of wheat, though it cannot, of 
■course, supply the place of the iaorqanic substances carried away 
in the hay crop. 
* Necessity has compelled me to sow rye-grass largely and repeatedly on soils 
too light and poor to grow clovers with any certainty ; but hitherto I have had no 
cause for regret. Under the management adopted the land has improved in the 
production both of corn and of green crops. The rye-grass is always folded off 
by sheep in hurdles and is stocked early, as soon as it begins to flower. With 
these precautions no evil results need be apprehended from this crop. In a moist 
season on a burning soil its produce will far exceed that of any other plant ; whilst 
the thick bed of roots which it leaves behind is of essential service in improving 
the mechanical condition of such a soil for the following corn crop. The evil 
influence of this crop depends on its seed being allowed to ripen, a process so 
rapidly performed as often to take the farmer by surprise. On the same soils all 
•attempts to grow rye as a green crop, whether for mowing or folding off, were 
attended with evidently injurious efi'ects on the following corn crop.— P. H. F, 
s 2 
