The Dupuyer acantha. [volume] (Dupuyer, Mont.) 1894-1904, 1897-09-02
culture

farmer or the h~orticulturist pro-
duces. If the quantity that the crop
can get of any one of them is too small
for the making of a good yield, the
yield will not be sufficient NO matter
how mich there may be of all the
others. If the quantity of IN OF
them is more than enough for a gooo
yield, it is only foolishness to supply
any more of that substance in lertii-
izers. The supply of water ana It's
constituents, and of carbon, are prac-
tically beyond the control OF the crop
grower except in so far as water may
here and there be supplied by irrlga-
ton, or may everywhere be conserved
by shallow surface tillage properly
managed. The supply OF lime is usu-
ally large enough in ordinary araDie
soils. Therefore only nitrogen, pnos-
phoric acid and potash are left to be
looked after; these, as every consumer
Of commercial fertilizers knows, are the
things that he pays for in whatever Oh
these fertilizers he buys. BY the IN
PRODUCTION of leguminous plants, such
as clover, vetch, lupine, peas, bean ana
the like, into his rotations, he may save
himself from the necessity OF buying SO
much nitrogen as he might otherwise
have to get in order to preserve the
proper balance of the plant foods in his
soils. These crops, as almost every
farmer knows, can get a part OF their
nitrogen from the air; and they will
in general get more of it from the air
and less from the soil the poorer the
soil is in available nitrogen. and the
richer it is within certain limits In
potash and phosphoric acid. Every
ordinary arabic soil has far more than
enough of nitrogen, p%hosphoric acid
and potash for the production of a good
many crops; and yet there are many
such soils which will not yield paying
crops unless fortified with one or more
of these very same plant foods. 1t may
be taken for granted that an acre of
most twelve inches at least $500 pounds
of nitrogen, 5000 Of potash and $500
of phosphoric acid. These quantities
are from so to 500 times greater than
those sold off the farm in any crop.
There Is at least so times as much nj
trogen in such a soil as is sold in any
part of any crop, and much oftener 100
or even 200 times as much. There is
at least 100 times as much potash as is
carried off the farm in any part of a
crop sold, and oftener 500 times as
much. Similar figures might be given
for phosphoric acid. Why, then, must
W. fertilize our soils in one way or an
other?
The one most important reason is
that these plant foods in the soil are for
the most part in an insoluble, or as
very commonly said, unavailable form,
and that they usually become available
only little by little each year. That
they do thus become gradually avail
able is clearly shown by some of the
experiments of Lawes and Gilbert, of
England; some of their plats have
yielded crops of wheat and other GER
calls now for fifty years and more,
without any manure. x may be, how
ever, that one of these foods does be-
come available year by year in large
enough quantities to contribute it's
share towards a good yield of some
crop, provided that there is enough of
the other two, but that there is in fact
not enough of the other two; or it may
be that enough of two of the foods will
become available fast enough each sea-
son for a good crop, but that the other
one will not; there will be only a poor
crop in either case.
There are cases in which it would be
only folly, with some thousands of
pounds of the one or the two foods in
the soil, and in such a condition that
the crop grown or it can get all it
needs for a good yield Cat least for one
year, and probably for the next year,
and even for a few years more), to buy
these foods in commercial manure; nor
would it be the height of wisdom to
keep putting them on the soil year after
year in stable manure since that also
contains the three foods under consid-
Grafton, as well as other useful sub
stances.