Science In Agriculture
I am not a scientific farmer; it is not probable that I ever shall be. I
have no such knowledge of Chemistry and Geology as any man needs to make
him a thoroughly good farmer. I am quite aware that men have raised good
crops--a good many of them--who knew nothing of science, and did not
consider any acquaintance with it conducive to efficiency or success in
their vocation. I have no doubt that men will continue to grow such
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crops, and to make money by agriculture, who hardly know what is meant
by Chemistry or Geology; and yet I feel sure that, as the years roll by,
Science will more and more be recognized and accepted as the true,
substantial base of efficient and profitable cultivation. Let me here
give briefly the grounds of this conviction:
Every plant is composed of elements whereof a very small portion is
drawn from the soil, while the ampler residue, so long as the plant
continues green and growing, is mainly water, though a variable and
often considerable proportion is imbibed or absorbed from the
atmosphere, which is understood to yield freely nearly all the elements
required of it, provided the plants are otherwise in healthful and
thrifty condition. Water is supplied from the sky, or from springs and
streams; and little more than the most ordinary capacity for observation
is required to determine when it is present in sufficient quantity, when
in baleful excess. But who, unaided by Science, can decide whether the
soil does or does not contain the elements requisite for the luxuriant
growth and perfect development of Wheat, or Fruit, or Grass, or Beets,
or Apples? Who knows, save as he blindly infers from results, what
mineral ingredients of this or that crop are deficient in given field,
and what are present in excess? And how shall any one be enlightened and
assured on the point, unless by the aid of Science?
I have bought and applied to my farm some two thousand bushels of Lime,
and ten or a dozen tuns of Plaster; and I infer, from what seemed to be
results, that each of these minerals has been applied with profit; but I
do not know it. The increased product which I have attributed to one
or both of these elements may have had a very different origin and
impulse. I only grope my way in darkness when I should clearly and
surely see.
An agricultural essayist in Maine has recently put forth a canon which,
if well grounded, is of great value to farmers. He asserts that the
growth of acid plants like Sorrel, Dock, etc., in a field, results from
sourness in the soil, and that, where this exists, Lime--that is, the
ordinary Carbonate of Lime--is urgently required; whereas the
application of Plaster or Gypsum (Sulphate of Lime) to that field must
be useless and wasteful. If such be the truth, a knowledge of it would
be worth millions of dollars to our farmers. But I lack the scientific
attainment needed to qualify me for passing judgment thereon.
There is great diversity of opinion among farmers with regard to the
value of Swamp Muck. One has applied it to his land to good purpose; so
he holds Muck, if convenient, the cheapest and best fertilizer a farmer
can add to his ordinary barn-yard manure; another has applied cords upon
cords of Muck, and says he has derived therefrom no benefit whatever.
Now, this contrariety of conclusion may result from imperfect judgment
on one side or the other, or from the condition precedent of the diverse
soils: one of them requiring what Muck could supply, while the other
required something very different from that; or it may be accounted for
by the fact that the Muck applied in one case was of superior quality,
and in the other good for nothing. Where Muck is composed almost wholly
of the leaves of forest-trees which, through thousands of years, have
been blown into a bog, or shallow pond, and there been gradually
transformed into a fine, black dust or earth, I do not see how it can
possibly be applied to an upland, especially a sandy or gravelly soil,
without conducing to the subsequent production of bounteous crops. True,
it may be sour when first drawn from the stagnant pool or bog in which
it has lain so long, and may need to be mixed with Lime, or Salt, or
Ashes, and subjected to the action of sun and frost, to ripen and
sweeten it. But it seems to me impossible that such Muck should be
applied to almost any reasonably dry land, without improving its
consistency and increasing its fertility. But all Muck is not the
product of decayed forest-leaves; and that which was formed of coarse,
rank weeds and brakes, of rotten wood and flags, or skunk cabbage, may
be of very inferior quality, so as hardly to repay the cost of digging
and applying it. Science will yet enable us to fix, at least
approximately, the value of each deposit of Muck, and so give a
preference to the best.
The Analysis of Soils, whereof much was heard and whence much was hoped
a few years since, seems to have fallen into utter discredit, so that
every would-be popular writer gives it a passing fling or kick. That any
analysis yet made was and is worthless, I can readily concede, without
shaking in the least my conviction that soils will yet be analyzed,
under the guidance of a truer, profounder Science, to the signal
enlightenment and profit of their cultivators. Here is a retired
merchant, banker, doctor, or lawyer, who has bought a spacious and
naturally fertile but worn-out, run-down farm, on which he proposes to
spend the remainder of his days. Of course, he must improve and enrich
it; but with what? and how? All the manure he finds, or, for the
present, can make on it, will hardly put the first acre in high
condition, while he grows old and is unwilling to wait forever. He is
able and ready to buy fertilizers, and does buy right and left, without
knowing whether his land needs Lime, or Phosphate, or Potash, or
something very different from either. Say he purchases $2,000 worth Of
one or more of these fertilizers: it is highly probable that $1,500
might have served him better if invested in due proportion in just what
his land most urgently needs; and I unflinchingly believe that we shall
yet have an analysis of soils that will tell him just what fertilizers
he ought to apply, and what quantity of each of them.
Science has already taught us that every load of Hay or Grain drawn from
a field abstracts therefrom a considerable quantity of certain
minerals--say Potash, Lime, Soda, Magnesia, Chlorine, Silica,
Phosphorus--and that the soil is thereby impoverished until they be
replaced, in some form or other. As no deposit in a bank was ever so
large that continual drafts would not ultimately exhaust it, so no soil
was ever so rich that taking crop after crop from it annually, yet
giving nothing back, would not render it sterile or worthless. Sun and
rain and wind will do their part in the work of renovation; but all of
them together cannot restore to the soil the mineral elements whereof
each crop takes a portion, and which, being once completely exhausted,
can only be replaced at a heavy cost. Science teaches us to foresee and
prevent such exhaustion--in part, by a rotation of crops, and in part by
a constant replacement of the minerals annually borne away: the
subtraction being greater in proportion as the crop is more exacting and
luxuriant.
What I know of Science applicable to Farming is little indeed; but I
know that there is such Science, and that each succeeding year
enlarges, improves, and perfects it. I know that I should thus far have
farmed to far better purpose, if I had been master even of so much
Science as already exists.
Understand that I am not a teacher of this Science--I stand very low in
the class of learners. I began to learn too late in life, and have been
too incessantly harassed by a multiplicity of cares, to make any
satisfactory progress. Any tolerably educated boy of fifteen may know
far more of Agricultural Science by the time he has passed his
eighteenth birthday than I do. What I know in this respect can help him
very little; my faith that there is much to be known, and that he may
master it if he will, is all that is of much importance. If I can
convince a considerable number of our youth that they may surely acquire
a competence by the time they shall have passed their fortieth year,
without excessive labor or penurious frugality, by means of that
knowledge of principles and laws subservient to Agriculture which their
fathers could not, but which they easily may attain, I shall have
rendered a substantial service alike to them and to our country.