Vermont phÅ“nix. [volume] (Brattleboro, Vt.) 1834-1955, 1883-08-31
Soil AnalyHis---Its NOrrhIessneEs as A
Guide in Agriculture.

DIR. Sturtevant of the New York agricultu
raj experiment station devotes his last bull. tin
to the subject of soil analysis. That he is not
much of believer in the practical value of
this application of chemistry to agriculture is
apparent. In explaining why the station has
refused to enter into this branch Of theoreti-
cal farming he says:
A cubic foot of soil in the average condi.
ton Of moisture weighs from ~ to 100
pounds. The soil taken 10 inches deep from
au acre of land would therefore weigh about
3.0OO,OO0 pounds. For the purpose of anal
ysis, in the ordinary method, about l 10 of IN
ounce of this soil would be taken, and TIN,
represents about l,4oO DOC, 600 part of al
acre.
If one ton of superphosphate, containing
10 per cent of phosphoric acid were thor
oughy mixed with the upper 10 inches of au
acre of soil we should have added POO pound-
of phosphoric acid TO 1900, 600 pounds Of
soil, or one part to 5000 that is to say. that
each $4,000 pounds of soil would contain one
pound of the added phosphoric acid. As but
ITO Of an ounce of this would be used fer
analysis, this lilo of an ounce would contain
but l-lj00 added parts of phosphoric acid
and this proportion would be represented by
the percentage figures 90. COGG, or .OOOOOG6 of
an ounce. This will be better understood if
we repeat that in percentage figures it would
require the addition of over 300 pounds of
the superphosphate to the acre to change the
third decimal figure of the analysis by unit
The corollaTy of this is that as the chemist
rarely works in this class of analyses beyond
the second decimal figure, the addition of an
ordinary fertilization, or that sufficient TO
make the difference between good and bad
crop, would not be detected. We can more.
over state the praptical i'm -
ing two samples of soil from different places
in the same field which would analyze alike
within even the second decimal figure.
In the beginning OF the application of sci
ence TO agriculture, the public attention was
strongly attracted by the theory that a chemi.
cal analysis of soil was about to offer a sure
means for determining definitely the condi-
ton and the needs of our soils, and various
Guardians disseminated the idea of this posi-
bility for purposes of their own, in order to
secure the privilege Of prescribing and fur
nishing the diet required for each field of the
farm. Those who should have known better
were 10th to appear in contradiction, for early
science Is presumptious, and not having as vet
determined its strength or its weakness, would
attempt by single bold and daring effort work
far beyond its capacity AT the present time
it is universally recognized by men of scien
tine training that the analysis of the soil for
the purposes of the individual farmer can offer
no solution to the problem of what fertilizer
or how much to apply.
While denying that analyses of soils can
give us definite information concerning their
productiyeness, and while asserting that the
teachings of experience have shown us that
in most cases there is no direct relation be-
tween the present analysis of soils and
the present agricultural value, or otherwise
expressed, test analyses cannot show with
certainty whether or not a soil is in condition
to yield full crop for the time being, vet we
would not deny that for the purposes of sci
ence such analyses may possibly be of some
benefit as Offering us a judgment of its gen
eral character, the mode of its occurrence or
of Injurious substances which at times it may
contain. 1t may also be Of avail to indicate
to US the changes produced in the soil through
the agencies included in the word cultivation.
A soil which contains the plant food sufH.
Gent for hundreds of crops, as determined by
analysis may yet be agroulturally barren
through the inability of the plants to reach
the elements which, although absolutely in