tire of clover. The several particles of earth, by 
the long, deep, and numerous radicles of these 
plants, become mechanically forced from their 
position, and their points of contact thus ren- 
dered fewer in number; and such soils compara- 
tively become specifically lighter in proportion to 
the weight of a determinate volume.” A scien- 
tific paper, by the Rev. W. Thorp, in the Journal 
of the Royal Agricultural Society of England, 
makes an able appeal to experiment, in vindica- 
tion of this opinion and in refutation of the pre- 
vailing opinions, and then shows how perfectly 
this opinion harmonizes with the numerous and 
hitherto perplexing phenomena of clover-sickness. 
The soils of the chalk, oolite, and magnesian- 
limestone districts of England, after losing their 
power of producing clover, re-acquire it by the 
enjoyment of a considerable period of rest. For, 
“the more frequently the clovers, or tares, or any 
large tough-root plant are sown, the less compact 
and lighter in weight does the soil become; and 
at length, there is produced from this cause an 
incapacity of the clovers growing upon them to 
resist the frost; yet, in time, by the decomposi- 
tion of these roots, and the cultivation of bulb- 
| ous-rooted crops, and the treading of the soil by 
sheep in eating them off, as is usually practised, 
reconsolidation of the soil takes place, and the 
same land is thus enabled again to sustain clover 
against the severity of the frost.” —In some fields, 
particularly on the wolds of Yorkshire, the clover 
sometimes remains alive and healthy on the 
headlands, after it has everywhere else perished ; 
and it appears to owe all its safety on the head- 
lands to the incidental circumstance of their hay- 
ing been trampled and comparatively consolidated 
by the horses when turning round in ploughing.— 
Clover after teazles invariably fails on the strong 
tenacious clay lands around Hemsworth ; and 
yet clover after teazles succeeds better than any 
other crop, in the magnesian-limestone districts, 
| particularly around Kirk-Smeaton. [For the 
| treading of the teazle-spittalers and reapers ren- 
ders the clay land so compact as to exclude the 
proportion of air necessary for supporting the 
clover ; while just the same thing renders the 
light and porous limestone sufficiently solid for 
| preserving the crop through the winter.—One 
| portion of a field which had received farm-yard 
manure in preparation for turnips has been found 
to maintain clover, while another portion of the 
same field which had received bone-manure in 
preparation for turnips has been found to let the 
clover perish; and the former of these portions 
seems to have owed much of its superiority to 
the binding or agglutinating action of the dis- 
solved dung, while the latter owed much of its 
inferiority to the loosening and separating action 
of the slowly decomposing bones.—Some parts of 
the magnesian-limestone districts will produce 
clover every fourth year, and others will produce 
it only every eighth year, others only every 
twelfth year, and others not at all; for “the 
CLOVER. 
825 
compactness of the limestone soils is very vari- 
able,—some require pressing for wheat, others do 
not,—some contain five per cent. of alumina, 
others not one per cent.,—some twelve per cent. 
of lime, others not two per cent.,—hence, upon 
the more compact the clover will stand the win- 
ter, while upon other portions it will not do so.” 
—TIn farms in the south of England which have 
a light and porous soil, a working flock of sheep 
very generally secure the successful cultivation 
of clover; for, by their treading and their drop- 
pings, they both consolidate the soil and increase 
its capacity for heat—The claying or marling of 
clover-sick lands in Norfolk frequently restores 
their power of bearing clover; because it so 
changes their mechanical texture as to render 
their particles cohesive, and their whole sub- 
stance less penetrable by frost—The chalking of 
the Yorkshire wolds, or the liming of many light- 
ish lands in other districts, is favourable to clover, 
—simply because it increases their tenacity ; and 
so sensibly has the chalking this effect, that a 
person, walking over almost any portion of the 
wolds may know, from the sensation of firmness 
or otherwise conveyed through his feet, whether 
it have been chalked—* Sprengel remarks that 
the clovers delight in a close-topped soil, or one | 
which admits no great quantity of oxygen to the 
roots. The best clover grown in Great Britain 
is upon the warp soil in marsh land near the 
river Humber; for not only is such a soil dry 
and compact, but abounds in microscopic animal- 
cule. Ehrenberg has discovered that the mud 
of the various harbours in Europe contains from 
one-third to half of its volume of distinguishable 
organic bodies, chiefly polythalamia, from the 
nitrogen of which no doubt these soils derive 
their general fertility.—The practical and very 
important inference from all this is, that ten- 
dency to clover-sickness may, in every instance, 
be successfully combated, and that, by rolling, 
pressing, claying, chalking, liming, or other con- 
solidating appliances adapted to the specialities 
of the various kinds of soil, it may be completely 
and quite cheaply vanquished. “I should say,” 
remarks the writer whom we have been follow- 
ing, “lime the clover-ley when broken up for 
wheat, press the wheat, and also press the soil | 
for barley, and after harvest, before November, 
roll the barley with a heavy roller, and the pro- 
bability is, that we should hear no more of clover- 
sick lands.” 
Red clover is always sown in spring, and very 
seldom sown alone. It evolves so small a bulk of | 
produce in the first year that it could not remu- 
nerate by being sown alone; and it enjoys posi- 
tive advantage from the presence of another 
crop, which shall not remain longer on the ground 
than till August or September; and in all ordi- 
nary cases, it detracts from the nourishment 
which the soil might yield to the accompanying 
and overshadowing crop, no more than it com- 
pensates by its own value. On strong clayey 
——— 
