Daily Kennebec journal. [microfilm reel] (Augusta, Me.) 1870-1975, 1913-05-08
Chemical Analysis Of Sells.

Since crnps derive SO large a pro.
portion of their food from the soil,
says l.. H Merrill, professor of asrit
cultural chemistry at the University III
Maine, lit is quite natural that We
should come to think of the chemical
composition of the soil as the correct
measure of its fertility. The uni
versity is frequently asked to make
soil ANALYSES and for some reason re,
quests of this nature have been un .
usually numerous during the present
spring. In many instances samples u
soil are forwarded. and SPECIFIC in1or-
nation is asked for, the writer stating
perhaps that he grew potatoes last
season. and wishes to SOW oats TINS
spring. The analysis in such cases Is
supposed to be trustworthy guloe III
the selection of a fertilizer. In other
cases the writer merely states thae
the soil in question failed to give good
returns last season, and he looks foi
an ANALYSIS to suggest remedy.
"A great many soil analyses have
been made. and the published results
deserve close study. One of the most
interesting facts which such invesu-
cations have brought to light is that
nearly every soil, even those incapa-
BILE of producing good crops, CONAN I
store of plant food far in excess OF the
needs of the very crops they !ali u
produce. A plant is able to take It's
food from the soil only in soluble
forms. while by far@the greater part III
the elements needed by crops exist III
the soil in the form of insoluble COM
mounds which are consequently not
available. chemical analysis simply
shows that they are there Up to the
present time the chemist has not oe-
vised a reliable method by when ne
can measure the availability OF THESE
materials to the plant. Even ne
succeeded in determining the availa-
biIitv for a certain crop, he would have
made but little progress since ne
might find it necessary to estaoilsh
different standard for every other rop.
The roots of plants take an active part
in dissolving plant food, and no Two
Kinds of plants possess this power III
the same degree.
"The importance of the quality
which we call availability may be il
Illustrated lnuS. suns Aiti'SHh's
over 1000 pounds of phosphoric acid ia
the upper six or seven inches ot al
acre. vet fail to produce good crops lei
want of this very compound. sup
posing now, we add to such a SOIL 4
Fertilizer carrying 10 per cent. aVah-
able phosphoric acid, applying 1t al
the rate of one thousand pounds to the
acre. and working it INTO the soli u
the depth of seven inches. The MAJ.
ton IF fertilizer carries one hund. III
mounds of available phosphoric acia,
which has become mixed with two
wilton mounds of earth. A little cai-
culation will show that we nave auoea
nbosnhoric acid to the extent OF one
half of one hundredth of one per cent.
IF such a soil were analysed be1ofe
and after such an application, an oroi-
nary chemical analysis would not de-
tect the difference. Yet in spite or
the fact that the soil may have already
contained two or twenty times thus
amount. the crop knows the differ
ence. 49,,
.vrhere is but one way to learn the
fertilizer requirements of the soil ana
that is nv close observation and car.
FIJI recommendation on the part Of the
man who tills the soil. If the apps
cation of potash salts alone produces
satisfactory results, nitrogen anu
nbosnhoric acid should not be used.
frhe indiscriminate use of complete
fertilizer, is fairly certain to increase
the crop. but the practice is In many
cases a wasteful one. The UNIVERSITY
holds itself ready to aid the farmer N
every way within its power, put Tor
the reason stated it cannot undertake
soil analyses.