The progressive farmer. [volume] (Winston, N.C.) 1886-1904, 1901-03-19
Agriculture.
Is THE BEST METHOD OF CONDUCT
ZIG EXPERIMENTS TO DETERMINE
.zTHE FERTILIZER REQUIREMENTS -
OF DIFFERENT PLANTS AND
SOILSl
- Of Director R. ]. Redding, Georgia Ex-
pertinent Station.

Il Is known to all intelligent farm
- +ba+ ordinary agricultural plants
~ r.mDosed of certain organic and
in,rranic elements, numbering four
+san in all. 1t is fact that all of
these elements are found in all agri-
,ritnral plants, and also in the bodies
ofsrf animals. The relative amounts
of each element vary considerably in
5iff4rrnt plants, and, within narrow
limits IN plants of the same species,
mr. even the same variety, when
er..ru under different conditions of
soil. climate and culture.
II 7s also we'll known that three of
these elements, tO-wit, phosphorus,
potassium, and nitrogen, are all that
we need concern ourselves about, be
csr-a Of their comparative scarcity
in +ne soil as compared with the re
manning eleven elements. These are
often called the valuable elements,
although the term COSTLY" or Eek
nen-lve" would be more accurately
5asrriDrive. since they are what the
farmer paws his money for when he
h7~sa 81 fertilizer. Lime and carbon
are lust as necessary to the growth
and development of a plant, or a
cr5p. as are phosphorus or nitro
ran Indeed. we're we to measure
the Importance of any one element
I'm pIant life bv the relative amount
that enters into the composition of
n7an+s we would at once place a
very high estimate on both lime and
carbon. But the TACT is that these
two are found in great abundance in
all ordinary soils, or, in the case of
carbon, in the air above and within
the soil.
The scientific agriculturist is we'll
aware that an average soil contains
81 very large store Of all the elements
u-cessary to the growth of crops and
the f5rmatiOn of plants. An acre of
average soil, taken to the depth of
inches. contains about 3, POO pounds of
nitrogen, 1000 pounds of phosphoric
acid and Is, 900 pounds of potash. 1t
IS quite an easy matter for the
analyst u find out its exact content
a- every one Of the element. 1t is
still easier to find out just what
amount Of each element is contained
-- Ii gwen plant or ii given total crop
If any kind. In the case of plants
L- .aDu0t tell Us the particular form
OF combination in which all these
elements enter into the plant struc-
rc-. Nor is this particularly desir-
a..- since the plant, during its
w ra and development selects
-. dement's as it needs, and by an
.-.mv If its own combines them
la into such forms as best meet
--. demands Of its own life and of
-- lie that is to subsist upon it.
b. even if we we knew exactly the
a...-eal composition of plant, or
..a crop. it would be no certain in
-..-.l 0f the amounts or proper
tins e the elements that should be
...- in the form of d fertilizer.
....~ and COW peas each contains a
..r.. ..rvcntage of nitrogen yet we
- ..er It Is not necessary to apply
-... a.n 10 these crops.
..- .U ANALYSIS of the soil does not
T.. reveal the exact forms and
-.aI combinations of the differ
e.. aaents. The very information
r.- ..roars most desirable is unat-
g.. e.. In the case OF plants the
-t may tell US some things that
ar. .. 40 especial value in this con
il. and which we do not care
E....raar.v to know. In the other
. #.e very things we are very
a.. - know he cannot tell US.
0.~sI analysis, alas, does not tell
-- ..t t.ercentage of the plant in II
iu form that Is Immediately
a-c to the crop. A soil may
r. ID he very rich according to
A., and yet yield very unsatls-
d. .. crops. On the other hand,
-- may indicate a relatively
.rccutage Of plant food present
g. IL. soil, and yet it produces large
.-. j am not myself an analytical
c.r"~-, ana therefore do not feel in
AL. degree responsible for the balk
t--t oar friends of the retOrt and
gs-..JIe make at this point.