174 
THE CULTIVATOR. 
Ipri^e (Sssflg. 
THE PREPARATION AND USE OF MANURES. 
BY WILLIS GAYLORD, 
Associate Editor of the Cultivator. 
(Concluded from page 159.) 
Lime _There is no substance, containing no animal 
or vegetable matter, which exercises a more powerful 
or beneficial effect than lime, in some one or all of its 
forms of carbonate, phosphate and sulphate. In the 
common form in which it is found, that of a carbonate, 
it acts in two ways, mechanically and chemically. Be¬ 
ing less porous than sand, and more so than clay, its 
mixture improves soils in which either of these prevail; 
while as an alkaline earth, it acts chemically on such 
animal or vegetable matters as may exist in the soil. 
Lime develops its chemical action most fully when in 
its caustic state, or when, by burning, the carbonic acid 
has been expelled, and the lime rendered what is termed 
quicklime. In this state, it dissolves such organic mat¬ 
ter as may exist in soils, and prepares it for the food of 
plants. Humus frequently exists in the soil in a solid 
and insoluble state; lime applied to this, renders it solu¬ 
ble in water, in which form it may be taken up by the 
roots of plants. A vast deal of needless controversy has 
been carried on respecting the value of lime as a manure, 
or the quantity which should be used per acre. By some, 
it has been extolled as the very highest on the list effec¬ 
tive manures; while others have decried it as of no use 
whatever; and both have appealed to experiments as es¬ 
tablishing their positions. A knowledge of the nature 
of the action of lime, would have prevented such seem¬ 
ing contradictions. “Lime in excess, forms, from the 
humus of the soil, an insoluble salt; and may thus, when 
applied to a soil abounding in salts of lime, or in which 
it already exists, be productive of injury, whatever may 
be the vegetable or organic matter of the soil. In this 
state of excess, lime converts, but at the same time locks 
up, the humus of the soil; when if applied in the right 
quantity, it would have been useful. Lime is of no value 
whatever as a converter, or produces no chemical effect 
in promoting growth, unless there is organic matter in 
the soil on which it can act. Lime is most efficient when 
used on soils full of insoluble humus, such as peaty mat¬ 
ter or woody fibre, but which, from the abundance of 
the tannin principle contained, resist the ordinary pro¬ 
cesses of decomposition.” There would seem to be no 
difficulty, therefore, in determining whether lime can be 
used on any given soil to profit. Indeed there are, it is 
believed, none where it would not be useful, except 
such as are already supplied with this carbonate, or those 
which are wholly destitute of vegetable or organic mat¬ 
ter. As a general rule, the greater the quantity of hu¬ 
mus in a soil, the greater the amount of lime which may 
be applied with benefit. As long as there is a store of 
organic matter in the soil, lime, if not in excess, is a 
valuable manure; but when this is exhausted, the appli¬ 
cation of lime only increases the sterility by destroying 
such efforts at vegetation as might in time, aided by light 
and moisture, partially remove the unproductiveness ex¬ 
isting. This fact may serve to explain some of the con¬ 
flicting statements that have appeared in the agricultural 
journals of our country, on the use of lime. Where hu¬ 
mus is abundant, the quantit}'^ that may be safely used, is 
very great; on soils already poor, a small portion siieed- 
ily exhausted the remaining powers of the soil. Lime, 
from its alkaline qualities, acts in neutralizing whatever 
free acids exist in soils, whether oxalic, phosphoric, ma¬ 
lic, or others. It acts also in decomposing some of the 
earthy or compound salts formed in the soil, and thus 
renders the geine held by them, available to the plant; 
but its great and most important use is in converting the 
insoluble organic matters existing, into soluble ones, and 
thus directly furnishing an abundant source of nutriment. 
Carbonate of lime is sometimes used pounded or broken 
fine; and in this state, its mechanical value is great in 
stiff or clay soils. Such soils too, usually abound in acids; 
and these gradually acting on the lime gravel, its chemi¬ 
cal effect is slowly but beneficially apparent. 
MARL. 
Marls, which exert so powerful an influence on many 
soils, derive most of their value from the lime they con¬ 
tain; and with few exceptions, their power as fertilizers 
may be measured by the per cent of lime shown on analy¬ 
sis. There are some marls, however, which are an ex¬ 
ception to this rule; their value appearing to depend on 
other matters than mere lime. Of this kind is the cele¬ 
brated green sand marl of New-Jersey, and some other 
points of the Atlantic coast. In this formation, which 
acts so powerfully as manure, there is from 6 to 10 per 
cent of potash; an agent, which, on light soils, is scarce¬ 
ly equaled as a manure. In addition to the lime w'hich 
marl contains, the influence of the proportions of sand 
and clay, of which the balance usually consists, must be 
taken into consideration in determining the value of this 
substance for particular soils. Thus, on heav')' or clay 
lands, marls abounding in sand will be found preferable 
to those the base of which is clay; and on light or sandy 
soils, the latter will be much the most useful, the per 
cent of lime in both cases being alike. Marl should 
be spread over the surface, and pulverized by the action 
of air and frost before it is plowed under. When so 
treated, experience proves it is a most valuable manure, 
and a single dressing exerts an influence for many years. 
PHOSPHATE OF LIME. 
Of another salt of lime, the phosphate, notice has been 
taken when treating of bones as a manure. It will not 
be amiss, however, to state here, that when any substance 
is invariably found in any part of a plant or plants, it is 
right to infer that the perfection of that part of the plant 
is impossible, unless the substance required is within 
reach of the plant while growing. Thus the stems of 
the grasses abound in silex; some of them, the cane for 
instance, to such a degree as to strike fire with steel, and 
unless this substance, in the form of silicates, was pre¬ 
sented to the plants, they would not be perfect. So it is 
right to infer that unless soils contain the phosphates, or 
a supply is furnished for the use of plants, that the cereal 
grains could never be perfected, as the seeds of these 
invariably contain large quantities of the phosphates. 
Phosphates are found more or less in all soils, and when 
these are deficient, bones form an abundant and accessi¬ 
ble source for their supply. It is also found in conside¬ 
rable quantities in all animal and farm yard manures, 
particularly in the liquid part. 
GYPSUM OR PLASTER. 
Gypsum is the third principal salt of lime which ex¬ 
erts a powerful influence on plants, and is one of the 
most valuable of all our mineral fertilizers. Much va¬ 
riety of opinion has been entertained respecting the man¬ 
ner in which it exerts its influence or produces its effects 
on plants; and these opinions can scarcely be said to be 
harmonized, even at the present time. Davy was in¬ 
clined to consider it a direct food for the plant, as it is 
found, to some extent, in those plants on which it exerts 
the most power. Chaptal referred its power to its sti¬ 
mulating agency on plants, produced by its action w’hen 
dissolved in water. Liebig ascribes its value to its giv¬ 
ing a fixed condition to the nitrogen or ammonia which 
is brought into the soil, and which is indispensable for 
the nutrition of plants. Dana, to the action of the lime 
and acid of which the gypsum is composed on the or¬ 
ganic matter and silicates of the soil. He says—“It 
seems almost incredible that so minute a portion of a 
mineral can act at all; yet how beautifully is the result 
explained by the principle that plants decompose first 
this salt; the lime, for plaster is a sulphate of lime, then 
acts on geine, which is thus rendered soluble; while the 
acid, the oil of vitriol or sulphuric acid, immediately acts 
on silicates.” It seems very probable that no single one 
of these suppositions will be found able to account in full 
for the action of plaster. That of Dr. Dana appears to 
approach as nearly to a solution as any of them, if we 
extend his term silicates so as to embrace those combi¬ 
nations formed by the union of the acid of the gypsum 
with ammonia, after its separation from the lime. If 
the action of plaster was due to its fixing ammonia alone, 
then it ought to be equally efficient at all times and pla¬ 
ces, which it certainly is not; or if it acted directly as 
nutriment, then its action would be as constant as that of 
rotted manure or compost, which farmers well know is 
not the case. Plaster does not act as usefully in the vici¬ 
nity of the sea, as in the interior; and onheav^y wet soils, 
is scarcely felt at all. Light sandy soils, or loamy ones, 
are those on which plaster acts the most sensibly; and 
clover, lucerne, potatoes, cabbages, and the leguminous 
plants, such as peas, vetches, &c., are the vegetables on 
which it exerts the most powerful influence. It is much 
valued as a dressing for wheat, not so much, perhaps, for 
its direct action on that plant, although that is not tri¬ 
fling, as for its effect in securing and promoting the 
growth of the clover and other grass seeds, usually, in 
wheat countries, sown with this crop. So marked is the 
influence it exerts in this respect, that plaster, clover, 
and wheat, are always associated in the mind of the most 
successful wheat growers; and its use is the most exten¬ 
sive in the best wheat growing districts of our country. 
In the minds of many, a senseless ])rejudice has existed 
against plaster, on the ground that it the more speedily 
exhausts the soil, and that the heavy crops at first ob¬ 
tained were the price of ruined farms. It is doubtless 
true that the man who uses plaster on his farm, who takes 
from his soils all he can get, and returns nothing to them, 
will soon find his soils worthless enough. He who in¬ 
tends to farm it in this way, should avoid plaster; but let 
any farmer alternate wheat and clover; husband and ap¬ 
ply his manures; feed off his clover in his fields, or to 
his stock in their stalls; let him not spare his gi-ass seeds 
in seeding, or his plaster in dressing, and his farm will 
never run down. Such men need not fear plaster. 
SALT. 
Common salt is an active and valuable manure, and 
has been used successfully as such, in all parts of the 
world where it can readily be obtained. In England, 
the pickings or impure salt is used for this purpose; and 
many experiments are on record to show that the effect 
is most marked and decisive. The following is one of a 
series of experiments instituted by Mr. Sinclair, to test 
the value of salt as a manure. The soil was light and 
grav'd ly. 
No. 1. Soil without any manure for 4 years. 
Produce per acre,.. 13 bushels, 26 lbs. 
2. Soil manured with stable dung to the 
previous crop, (potatoes,). 26 do. 52 do. 
3. Soil with 5 bush, of salt per acre, and 
no other manure for 4 years,. 26 do. 12 do. 
In the opinion of Mr. Sinclair, the effect of salt as a 
manure was to lessen the produce of straw as compared 
with other manures, and to increase the weight of the 
grain. 
Prof. Johnston has done more than any other person to 
extend the use of salt as a manure, by giving to the world 
his excellent Essay on salt used on soils, and the mass of 
experiments he has recorded. It appears that salt in small 
proportions, promotes the decomposition of animal and 
v'egetables substances; that it destroys vermin and kills 
weeds; that it is a direct constituent of some plants, and 
therefore necessary to their perfection; that all cultiva¬ 
ted plants of marine origin contain it, asparagus for in¬ 
stance ; and that all such succeed better when watered 
with salt water, than when deprived of it; that salt pre¬ 
serves vegetables from injury by sudden transitions in 
temperature, salted soils not freezing as readily as those 
to which salt has not been applied; and that it renders 
the earth more capable of absorbing the moisture of the 
atmosphere. When salt is applied as a manure, it may 
be used in quantities from six to fifteen bushels per aero; 
although some have gone as high as 50 bushels. Farm¬ 
ers, however, should be cautious how they venture on 
excessive doses, as an extravagant one could scarcely fail 
of being fatal to any crop. Legrand, in his experiments 
with salt, found that it gradually improved the crop of 
barley until sixteen bushels per acre was reached, when 
it gradually diminished until the amount of forty bush¬ 
els per acre was reached, when vegetation was destroyed. 
Salt combined with manure, has proved very efficient; 
and in the Woburn experiment, the wheat so treated ex¬ 
ceeded all others. The most favorable proportions were 
found to be 45 tons of dung, and five and a half bushels 
of salt per acre; the manure plowed in, the salt sown 
with the seed. The experiments that have been made, 
would seem to indicate that a preferable mode of using 
salt, in most cases, would be to sow it on the land some 
weeks before the seed is to be put in. In this case, 
where lime exists in the soil, a chemical change laltes 
place, at least partially, and muriate of lime and soda is 
the i-esult. Such a change would seem to be most fa¬ 
vorable to vegetation. 
SALT AND LIME. 
Salt and lime, artificially mixured as a manure, promi¬ 
ses to be a valuable aid to the farmer in those positions 
where the soil abounds with insoluble silicates or geine, 
and where other manures necessary to produce decom¬ 
position or fermentation are not at hand. Prof. John¬ 
ston recommends a mixture of two parts of lime and one 
part of salt, the mixture to remain incorporated in a sha¬ 
dy place, or covered with sods two or three months be¬ 
fore using. Salt and lime should not be used immedi¬ 
ately after mixing, as bad results are apt to ensue.; but 
after being well mixed in a dry state and lying as direct¬ 
ed, it may be applied at the rate of from thirty to sixty 
bushels per acre, either before or at the time of sowing. 
Mixed with soot, salt acts with great power on roots. 
Mr. Sinclair mixed six and a half bushels of soot with 
the same quantity of salt, and used the mixture on lands 
sowed to carrots. The result was, that unmanured land 
gave twenty-three tons of roots per acre, and the ma¬ 
nured yielded forty tons per acre; and Mr. Cartwright 
found that where unmanured soil gav'e 157 bushels of po¬ 
tatoes per acre, 30 bushels of soot and six of salt, made it 
produce 240 bushels per acre. Dr. Dana furnishes so 
beautiful an explanation of the manner in which this ma¬ 
nure acts, that it deserves a place entire: “By mixing 
quicklime with common salt, its soda is let loose, the acid 
combines with the lime, forming a soluble salt of lime, 
and so long as the soda remains caustic, it has no effect 
on the muriate of lime, but as soon as the soda becomes 
mild or carbonated, decomposition of the muriate of lime 
is produced, and the common salt regenerated. Com¬ 
mencing then with quicklime and salt, w'e pass to a solu¬ 
ble salt of lime and caustic soda, and from that to mild 
soda, and to carbonate of lime and the original salt. If 
these various changes talie place in the midst of peat or 
geine, it is evident that the caustic soda acts upon the 
geine, and also evolves ammonia from that substance; 
secondly, that the muriate of lime, in its finely soluble 
state, insinuates itself among the particles of the geine; 
that the soda is also equally diffused, and that when the 
soda becomes carbonated, it produces an almost impal¬ 
pable carbonate of lime throughout the whole mass, 
which, by its equal diffusion through the soil with the 
geine, acts upon the silicates, as has been heretofore ex¬ 
plained.” To produce these effects. Dr. D. directs to 
take one bushel of salt and two bushels of lime; to make 
the salt into strong brine, and with it slack the lime. Mix 
both well together, and let them remain ten days; then 
let them be well mixed with three cords of peat, shovel¬ 
ed well over for about six weeks, when it may be used. 
A quantity of salt sufficient to destroy all vegetation, may 
be applied to a soil with safety when a few months are 
to elapse before the crop is to be put on; as the chemi¬ 
cal changes which take place, partially neutralize its ef¬ 
fect during this time. A small quantity mixed with the 
soil in each hill of corn, has been found to protect it from 
the wire worm and the cut worm; indeed there is no 
substance that insects of all kinds more dread than salt. 
It is probable, therefore, that further experiments will 
show that not the least value of salt is to be found in its 
]U’eventive properties against these depredators. 
CHARCOAL. 
Charcoal is a v'aluable manure, and applied directly to 
the soil in a pulverized state, pi’oduces excellent effects. 
It acts by rendering the soil more permeable to atmos¬ 
pheric air, by absorbing and retaining for the use of 
plants the ammonia of the atmosphere, or such as falls 
in showers; by rendering soils with which it is incor¬ 
porated warmer; and by furnishing a constant supply of 
carbonic gas to growing plants. The great productive¬ 
ness of what are called coal hearths, or those places on 
which charcoal has been burned, has long been a com¬ 
mon remark, but this has been commonly attributed to 
the ashes, burned earth, &c. on such spots, rather than 
the coal. The use of coal alone, how'ever, shows that 
thou°-h these other matters are not without their value, 
the great additional fertility of these places is mostly 
owin'^ to the coal. Immense quantities of this substance 
are w'asted in the vicinity of forges, furnaces, smith's 
shops, &,c. which would be of great value, were farm- 
