The Pacific commercial advertiser. [volume] (Honolulu, Hawaiian Islands) 1885-1921, 1904-02-01
PAPERS READ BEFORE
FARMERS INSTITUTE

pilates added are available and the
crop responds at once. The question
is not, what elements and how much
does the soil contain, but how much of
these elements are available to the
growing crop?
With your experience I think that
you will agree with me that the ele-
ments in the Wahiawa soil are not in
a very available form, and 1 can ex-
tend this knowledge by saying that
this is true of most Hawaiian soils,
and especially of those soils subject to
a heavy rainfall.
Addressing myself to local condi-
tons, the Wahiawa soil, especially in
the upper portion of the lands, is
somewhat acid. This has been cor
rected by clearing, destroying the
natural vegetation, and turning over
the soil and exposing it to the air.
The acidity would be more rapidly and
effectively corrected by an application
of lime. The lime can be applied as
ground coral, which is the cheapest
form, or caustic lime. Either will COR
rect the acidity and add a store of lime
which will benefit the soil in many
ways, but caustic lime will also act
upon the organic matter. rendering
part Of the nitrogen available. Be-
sides this, plant food becomes more
readily available in soils literally sup
piled with lime, and it is one OF the
elements that heavy irrigations Of
rains wash out of the soil.
While phosphoric acid is not in
readily available form in the soil, crops
do not take off a great deal of it, and
it is not supplied, therefore, in artif1-
eial fertilizers in very large quantities.
Certainly, cane growers are not using
by any means as much phosphoric acid
per ton of fertilizers that they used,
say ten years ago.
The elements, potash and nitrogen,
are of more Importance here than
either lime or phosphoric acid While
the potash content of most Hawaiian
soils is satisfactory, it is singularly
unavailable, and crops remove large
quantities of it. The amount of potash
rerr owed by such crops as wheat, oats,
barley, etc, is three or four times as
much as the phosphoric acid, and it
should, therefore, be supplied literally.
This is especially the case with fruits
and vegetables. Large quantities of
potash are found in the ends of plants
and in fruits and very beneficial effects
nave been derived from liberal guam
titles of this element. It also does we'll
with plants Of large leaf surface and
with leguminous plants, such as peas,
vetches, etc. Recognizing your local
conditions and the crops that you
grow, I have always recommended
liberal amounts Of potash in the fer
tilizers
Nitrogen Is another very essential
element, and it has the disadvantage
of being the most costly. There are
three chief sources of nitrogen supplied
to the agriculturist. nitrate of soda
from Chill suIphate of ammonia from
the gas works of England, and bones,
blood. ETC., from the slaughter house.
OF the three forms, nitrate Of soda is
the cheapest and it has the advantage
of being readily soluble and available
to the plant. But it has the disadvan-
tage of being easily leached from the
soil either by heavy rains or heavy
irrigations. It should be used but
rarely in regions of heavy rainfall, and
in lands that are literally irrigated it
should be applied after irrigation, and