The Spectator. (Ozark, Ark.) 1911-1916, 1914-09-29
BY Prof. Il. a. Huston.

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Various Suggestions have bsen mad
In regard to the steps tagnIf n ~
formers In reference to tho q tAge
Of Potash in their fertilizers. ceused
by the greatly reduced sl1ipmetSts ~
Potash from Germany since tho drs1
OF August. Most OF the Fertilizer Com
panies have endeavored to make the
Potash on hand go as far as possible
by selling for the present brands OF
complete fertilizers containing only
or per cent OF Potash and withhold
ing from sale brands containing larger
amounts. 10y
The suggestion that some or all OF
the Potash be replaced by phosphoric
acid is absurd. for every schoolboy
knows that one plant food cannot take
the place of another There are some
indirect fertilizers, such as lime. gyp.
sum and salt that can release limit
ed amount of Potash from some soils
that contain hydrated silicates Of Alu-
nina and Potash But if these soils
have already been treated with lime
or have received repeated dressings
of the usual forms of fertilizer con
tanning soluble phosphate with its ac-
companying gypsum, then the Potash
in the hydrated silicates has to large
extent already been replaced and the
use of more lime or gypsum or salt
could not, be expected to release much
additional Potash Ground limestone
or oyster shells act too slowly to be
used as Potash releasers.
The residue Of soda left In the soil
by nitrate of soda is more effective in
releasing Potash than is gypsum and
hence goods. in which the nitrogen is
largely in the form OF nitrate of soda,
may have a special value In the pres
ent emergency.
1t is often stated that decaying or
ganic matter releases Potash from the
soil, but there seems to be no direct
evidence of this. On the contrary,
DR.. s. Peacock states In the American
Fertilizer OF Sept. 5. 1914. Several
thoroughly competent researches have
shown that decaying organic matter
has little effect on converting liner
mineral plant food in the soil int
available form"
In any soil the amount of Pota
capable Of being released by these In
direct means Is a very small fraction
of the total Potash In the soil, most
Of which exists In a form about as
soluble as window glase. There is no
known profitable method for render
ing this inert Potash of the soil avail
able fast enough to provide for profit
able crops. Whatever temporary ex-
pedients we may employ in the pres
ent emergency, we must keep in mind
that the Potash thus removed from
the semi-available soil reserves must
later be replaced il We are to main
tain the soils productiveness.
There is danger In the statement
that farmers have been using an ex-
cess of Potash. Crops use on the av-
erage about two and one-half times as
much Potash as phosphoric acid. while
the average fertilizer sold contains
only half as much Potash as phos-
phoric acid; yet no one claims that
we are using too much phosphoric
acid. The Potash remaining from pre-
vious fertilization is practically moth
ing except in the limited areas where
ton or more of fertilizer has been
used per acre on truck crops. Very
rarely is half as much Potash applied
to the wheat, oats. corn or cotton crop
as the crop removes.
The Potash mines are so numerous
and the stocks on hand so large that
supplies can be promptly sent for
ward, as soon as European conditions
permit freight shipments to be re-
sumed.