The morning news. [volume] (Savannah, Ga.) 1887-1900, 1893-03-27
Available Fertility In Soil,

No naturally fertile SOIL by which we
mean soil that abounds in the mineral ele
ments Of plant food, ever becomes entirely
exhausted, says the American Cultiudtor.
As cultivation decreases the proportion OF
vegetable matter the land becomes hard,
cloddy and not easily permeable to air and
water, the two agents that chiefly aid in
making plant food available for the roots of
plants 10 feed on. Under such conditions
the soarcer and more costly mineral ele-
ments assume insoluble forms. Analysis of
the soil shows them still present. but each
year TOO small proportions OF these minerals
lecome available, and the cropis q COMPARE
tive failure
Barnyard manure, of course, il the sta
pie remedy for these conditions. BY restor-
ing vegetable matter to the soil in form
likely to rapidly ferment it sets loose car
bonic acid gas, one of the very best solvents
Of mineral manures. 1t IS the carbonio
acid gas taken IN by snow IN its passage
through the air that gives the water from
melted snow such superiority for cleansing
dirt. 1t is better even than freshly fallen
rain water, al the snow in passing through
the atmosphere exposes a larger surface to
it, The gardener who waters his plants
with water from a cistern does not give
them the proportion of carbonic acid gas
that they get in showers or light SHOWS. 1t
is becoming known that by putting small
quantities of csrbonic acid gas in water
used for irrigation its likeness to rain water
and its value may be greatly increased.
There are other ways, however, Of in
creasng cerbonic acid gas in the soil. I'm
derdrainiDg is one of these, and, indeed is
the most necessary. 1t allows not merely
the water that falls on the surface to sink
through the soil, but by providing outlets
beneath as it disappears in the drain air
takes its place, and its oxygen attacks
whatever vegetable matter the soil con-
tains and turns it into carbonic acid gas.
THIS decomposition of air in the soil creates
some heat, as lis in fact process of slow
Burning. Hence it warns the soil, and
this of itself makes its mineral plant food
more available
We suspect that the advantage from use
OF salt in some cases, and its little value as
manure in others, depends on whether it can
tind In the soil any elements that need to be
made soluble. Salt, in the small amounts
that are usually applied to land, hastens
rather than prevents decomposition. 1t is
thus help In creating carbonio acid gas
wherever it can find material to decompose.
The salt itself is also decomposed and may
thus furnish an ineppreciable amount of
carbonic acid gas. Its greater help comes,
however, from its ability to aid the decom-
position OF mauures and in furnishing the
eolVenJ 10 keep mineral tertlllZers from re-
verung to lnsoluble conditions.
1t is quite probable that much phosphate
soon passes beyond the condition in which
1t can be used. W lille there is nothing in
salt to take the place OF phosphate, it may
be better to make phosphate in the soil
available than an extra supply OF that min
eral Potash, especially in the form Of wood
ashes, has also the same effect, with the adj
Vautage that thea ashes, besides furnishing
csrbonlc acid, are themselves supplier of
potash, one of the direct constituents Of all
plants. Wood ashes are a necessity to the
Vineyardist and orchardist. Possibly farm
ers raising crops that require less potash
can keep their soil fertility available, for a
Time, at least, more cheaply by the use Of
salt. But Whenever the time comes that
potash is exhausted. as it is apt quickly to
be on sandy or gravelly soils, salt will no
longer be OF any benefit, and resort must
De bad to supplies Of potash.
IL Is well Tor farmers to experiment with
tnelr land to ascertain what means of filing
IL with carbonic acid gas is cheapest and
most available. For though this gas in the
soil does not itself become plant food it is
the lack that more than any other fits what
Is In the soil for available use. Draining,
the use OF stable and green manures, and OF
such solvents as salt and potash, are each
anu all good in their places. Which will do
Tue work best is to be determined in each
vase only by practical experiment.