| 
as 
all the immediate purposes of pasturage. 
824 
has been thought advisable to add a few pounds 
more, to provide against contingencies ; when 
drilled, of course, the quantity required will be 
less, and it may be increased or lessened accord- 
ing to the nature of the climate and soil.” 
White clover has neither a proper habit nor a 
sufficient productiveness to be grown either as 
an independent crop or asa member of any course 
of alternate husbandry; but it is eminently suit- 
ed for herbage in any kind of pasture or grass 
lands, and ought always to be mixed in tolerably 
large proportion with the artificial grasses, in 
laying down land to what is technically called per- 
manent pasture. Though creeping and of low 
growth, it luxuriantly intertwines with the grass- 
es, so as to form athick and massive mat of herb- 
age; and it is at once so sweet and so very 
nutritive as to serve, in the highest manner, 
Yet 
when any instance of “permanent pasture” is 
intended to be of comparatively short duration, 
and to serve quite as much the remote purposes 
of an arable rotation as the immediate purposes 
of grazing, white clover is much less suitable 
than perennial red; for not only is it slower of 
development in the earlier periods of its growth, 
but it exerts a far feebler manurial power upon 
the soil for the succeeding cereal crops. Its pro- 
per place and treatment, therefore, are prominence 
among the grasses of a long continuance of arti- 
ficial pasture, and intermixture with the seeds 
of those grasses at the time of their being sown. 
It flourishes upon almost any soil, no matter how 
heavy, provided it be sound and dry; but it 
thrives best upon light calcareous soil; and, in 
very many instances, it springs, as if spontane- 
ously, from seeds which have been dormant for 
ages, either after the turning up of light calcare- 
ous land which has long lain in waste or neglect, 
or after a smart and prolonged action of calcare- 
ous manure upon other kinds of land. 
Red clover is an important element in all good 
alternate husbandry; but has. in a considerable 
degree, come to be distrusted, or to be considered 
as precarious, in consequence of having generally 
been cultivated on too close and routine a sys- 
tem, or at too rapid intervals. On its adoption 
into British agriculture, it exploded the old tri- 
ennial system, and led the way to all the valuable 
modern improvements in courses of cropping ; 
and its presence or absence, its prominence or 
obscurity, its profusion or sparseness in any dis- 
trict, is still a very distinct indication of the ex- 
cellence or wretchedness of that district’s hus- 
bandry. It affords ample support to the remu- 
nerating practice of soiling cattle, and, with the 
aid of tares, may form a sufficient supply of green 
food for all stock from the beginning of May till 
the end of November; it so covers the ground 
with its broad foliage, as to smother annual 
weeds ; and it so enriches the soil by the fixation 
of gases, and the profuse ramification of its roots, 
as to act with the power of a fallow, and make 
CLOVER. 
both a mechanical and a chemical preparation for 
a beautiful and luxuriant cereal crop. But when 
frequently repeated, or when grown at regularly 
recurring intervals, without efficient means being 
used to counteract the mischief done to the soil, 
it is, in numerous situations, exceedingly liable 
to serious and even very signal failure. In Bel- 
gium, it cannot, under the present system of 
Flemish husbandry, safely recur oftener than at 
intervals of eight or ten years; in Norfolk, it 
ought, according to the locally approved system 
of rotation, to recur in every fourth year, but 
frequently requires to be either substituted by | 
grass-seeds or pulse, or nursed and protected by 
a special application of mineral manure ; in the 
magnesian-limestone districts of England, it fails, 
on the average, to the amount of about four- | 
ninths of the entire surface on which it is sown; 
in the oolitic districts, and in such parts of the 
coal and the new red-sandstone districts as have 
a light soil, it is esteemed precarious at a shorter 
interval than about twelve years; and on the 
chalk wolds of Yorkshire, it has so often and egre- 
giously failed as to have become almost totally 
abandoned. In the last of these districts, in- 
deed, even white clover, when grown as a substi- 
tute of the discarded red, very often fails to the 
amount of one half of the surface sown. 
A crop of red clover which fails in consequence 
of too frequent sowing, or in the manner of what 
is technically called clover-sickness, springs up, 
and vegetates till after the harvesting of the 
cereal crops with which it was sown, and then 
dies away during the months of October, Novem- 
ber, December, January, February, and March. 
The cause of its failure has been a subject of 
great bewilderment to farmers, and of much 
controversy among scientific agriculturists. A 
somewhat favourite opinion ascribes the failure 
to an exhaustion of some constituents of the soil, 
which are required for the sustenance of clover, 
and points to a manurial supply of these consti- 
tuents, particularly of gypsum, common salt, and 
phosphate of lime, as a means of preventing the 
failure; and another opinion, with nearly equal 
plausibility, ascribes it to the presence of some 
vegetable excretions which are poisonous to 
clover, and points for a remedy either to the 
chemical decomposition of the offensive matters, | 
or to the avoiding or modifying of the particular 
crop by which they are deposited. But the chief | 
cause, and probably the only one, appears to us 
to be the destruction of the cellular tissue of the 
plants by frost,—or remotely the absence or con- 
siderable diminution of the soil’s cohesiveness, 
and of its consequent power of retaining heat. 
“Those plants, particularly clovers, which are 
impatient of sudden change of temperature, are 
readily destroyed by the frost; and soils, by the 
growth of white clover, red clover, and tares, be- 
come more pulverulent, puffy, and less cohesive, 
in proportion to the frequency of the growth of 
these crops; and this explains why these lands 
| 
ae eee nr rn a 
