The herald., 1896-12-05

BEST RES OLlS
written by the editor for the fifth bl-
ennial report for the State Board or
Horticulture by special request')
The exhaustion of the soil though the
culture of any crop is involVeo IN liiols
or less mystery. and is little understood
In the abstract or from chemical stand
point, although from a practical stand
point the matter of maintaining the
original integrity of the soil, and, in
fact, the building up of poor SOIL is
we'll understood and readily accom-
plished.
To give an illustration, let us look at
the orange. In an orchard in the san
Gabriel valley the soil analyzed LA per
cent in potash. Taking the soil to depth
of only two feet an acre of ground would
contain about 100 900 pounds of potash.
This potash would be enough to supply
an annual crop of 10000 pounds of
oranges for more than 2000 years. The
figures from which the above conclu-
sion is drawn are taken from the report
of the state analyst. Before the orchard
was fifteen years old it showed marked
signs of degeneration. The practical ap-
plication of potash in conjunction with
nitrates and phosphates some five years
ago revived the orchard and the annual
APPLICATION of complete fertilizer has
since kept it in a most fiourishins con-
dition.
Again. it is a we'll known fact that in
new ground. suited to the purpose that
from 400 to 800 bushels of potatoes can be
raised the first year, the second scar
scarcely one-half that amount can be
raised. and the third year the field would
hardly give it's seed back, and yet the
soil of such a field would analyZe prac-
tically the same at the end of the period
as it did at the beginning. Neverthe-
less the soil Is exhausted from the prac-
tical standpoint of the farmer; that is,
he cannot raise a paying crop of potatoes,
and yet from the standpoint of the
chemist the soil is as rich in plant foods
as ever, the little that would have been
withdrawn by three such crops as are
above described being only the 10000th
part of the plant food in the soil.
What is true in regard to the eXhaus-
tiOn of the sol, by an orange or potato
crop is also found to be true in practice
in regard to the walnut.
Chemical science has settled the facts
that nitrogen, phosphoric acid and
potash are the only three expensive ele-
ments that any soil is likely to become
deficient in: therefore, as general rule,
these are the Only elements that must be
added In order to do everything that is
known to science in order to properly
feed any crop. In order, however. to
make these elements. when applied,
most effective, the soil must contain
vegetable or animal matter).
1t is a we'll known fact that the best
results are attained in horticulture
where circumstances permit of a rota-
ton of crops, the same crop not being
reached oftener than once in four or five
years. In an orchard it is impossib BILE to
rotate crop, as the trees are set for a
lifetime. but the next best thing to a
rotation is in keeping up a rotation of
green crops for piowing under. and in
this way keep supplying the humus and
nitrogen al nominal cost. These crops,
of course, are planted during the fall
and grown at a time when the tree is
dormant.
In order, then, to get the best results
from walnut orchard two things are
necessary: First. prohibit the soil from
becoming exhausted. and. second, keep a
due amount of humus in the soil
The first proposition can be done by
applying annually these elements in the
proportion in which the crop, the wood
and leaf growth may remove them. 1t
would be both amusing and interesting
for rich chemist. with little to do and
who might own walnut orchard, to as
certain these facts by collection of all
the leaves. the new growth and crop
over a series of years, and his report
might be most interesting to the few
chemists who would read it. but the
farmer could scarcely keep awake over
which and how much of the essential
elements need to be added and the cost
of such application. To this question the
answer can be given by the crop and
trees themselves although the expert
ments have not been carried over a series
OF years, but for two succeeding years
excellent results have been attained by
using to every four pounds of nitrogen
nine pounds of phosphorc acid and Ave
nve pounds of potash in the form of
muriate. The phosphoric acid should be
in the form of super phosphate that is
treated with sulphuric acid which rem
ders the phosphate readily soluble in
water. so that it may be Immediately
available
A ton of fertilizer containing the fertil
zing elements in the above proportions
OF per cent nitrogen, per cent phos-
phoric acid and per cent potash should
not be worth to exceed $35 freight maid
Now as to the amounts to be appljed
Five pounds to tree three years old ap-
pears to be the limit from which anv
good can be derived; twelve pounds to
an eight-year-old orchard produces good
results, some of the trees yielding a
hundred pounds and all the trees aver
aging over seventy-five pounds of nuts.
on eighteen -year-old trees twenty-fve
pounds to the tree was applied with sat-
isfactory results. Taking the case of the
ght-year-old trees the cost of fertiliz
ing an orchard. where the trees were
twenty eight to the acre would be s5 60
or about 31a per cent of the value nj the
crop. ~
UNITED STATES PARTMENT OF,
AGRICULTURE.
DIVISION OF ENTOMOLOGY.
Washington, D. c.
NoVem Der 21st, 1896
Ny Dear Doctor:
l am going to put your offer of assist
Inv a-lyi