The Delta independent., 1925-02-13

Commercial fertilizers do not give
entirely satisfactory results on soils
which have long been in continuous
cultivation without having received
applictions of barnyard manure or
having had green crops turned over:
In other words commercial fertiliz-
ers with the possible exception of
nitrate Of soda and sulphate of am
monia are so slowly dissolved in soils
deficient in organic matter that
plants are unable to derive full value
from them.
So commercial fertilizers only give
maximum results on soils which re-
ceive frequent applications of manure
or land recently broken from alfalfa,
or on land where green crops have
been turned over. The elements of
plant food most frequently deficient
in soils are nitrogen, phosphoric acid
and potash.
Nitrogen.
This food element stimulates the
growth of leaves and is especially
important in the growing of such
crops as lettuce, spinach, cabbage,
etc. It is also of value in giving all
plants a quick start in early
summer. If used abundantly in late
season it stimulates late growth and
retards maturity.
Commercial Sources of Nitrogen.
Nitrate of Soda chemical salt
containing approximately 1870 of
nitrogen. A very quick acting ferti-
lizer which should be applied after
the crop is planted and growing 1t
teaches from the soil quickly under
irrigated conditions and the seasons
supply is best applied in two or three
light applications rather than one
heavy one.
Sulphate of Ammonia-A salt usu-
ally containing about 2Oqo of nitro
gen. A very quick acting fertilizer
not so easily washed from the soil as
nitrate of soda. 1t also leaves an
acid waste material in the soil and
for this reason is better adapted to
lands naturally alkaline. Nitrate of
sodo leaves an alkaline residue and
tends to increase the alkali in the
SUI Mllllt oulpllsilt VI tllllllOuld ltuub
to neutralize it. Sulphate of am
monia will have the better effect on
most of our Colorado soils.
Dried Blood-An organic form of
nitrogen less readily available than
the first two mentioned In other
words it can be applied to the land
at the time of preparation for seed
ing and in sufficient quantities for
the entire season. The commercial
product commonly contains from s to
go of nitrogen and frequently as
much as g. to 40 of phosphoric acid.
Fish Meal-This product varies
with the source but usually COM
pares with dried blood in fertilizer
value both in nitrogen and phosph-
oric acid AS a rule the product
varies more in composition than dried
blood and should be purchased on a
fertilizer guarantee. 1t is much like
dried blood in rate of availability, and
is commonly applied at the time of
preparing the land.
Cotton Seed Meal-A by-product of
cotton seed oil manufacture. Pound
for pound it has a fertilizer value |
about the same as dried blood or fish
meal and should be used the same.
1t usually carries from to 20 of
nitrogen, about 31s of phosphoric acid
and 20 of potash.
Phosphoric Acid.
The element is used by plants in
the building up of stems and roots,
and more especially seeds. 1t is
fertilizer that is not easily washed
from soils. The rate at which 1t be-
comes available to plants varies with
the form used but it is a relatively
slow acting fertilizer and all forms
may be applied in early spring at the
time of preparing the land for plant,
ing.
Commercial Sources of Phosphoric
Acid.
Bone Meal-Commercial forms of