The Ladysmith news and Ingram news. [volume] (Ladysmith, Wis.) 1905-1906, 1905-10-07
M1ESCEH,I.AN
Soil Fertility in the Corn Belt.

Articles have recently appeared in
several agricultural journals suggest
| ing that the total plant food content
of the soil is essentially permanent
| theory which is liable to mislead the
farmer and injure the farm. For ex-
ample, take the following statements
quoted from a Delaware station bulle-
| tin:
''An average of the results Of 40
analyses of the typical soils of the
United States showed per acre for the
first eight inches of surface $500
pounds of nitrogen, 2,100 pounds OF
phosphorus, and LOO pounds of po-
| tassium. The average yield of wheat
in the United States is IA bushels per
| acre. = Now if all the poten-
tial nitrogen, phosphorus, and potas-
SUM could be rendered available there
| is present in such an average soil, in
the first eight inches, enough nitrogen
to last 80, enough phosphorus for 500,
and enough potassium for 1000
years."
Who wishes to raise only IA bush
to raise 40 bushels and possibly we
shall then get 80 bushels. The aver
age yield of corn in Illinois is 80 bush
els, but those who prepare to raise
100 succeed in getting rs bushels per
acre.
The average soil of the corn belt
| does not contain 2,100 pounds of phos-
phorus per acre in the surface eight
inches, but only about $500 pounds of
total phosphorus to that depth. A
100-bushel crop of corn requires 23
pounds of phosphorus; consequently
| the total phosphorus content of this
| surface soil, instead of being sufficient
for 10000 crops or for 500 crops, is,
as a matter of fact, sufficient for only
| 70 crops of corn of 100 bushels each.
| On the other hand the nitrogen con-
| tent of the Illinois soil, instead of be-
| ing only 1900 pounds, is about 5000
pounds per acre to a depth of eight
| inches; and where clover or other
legumes are being grown in rotation
or as catch crops, the supply is being
to some extent at least renewed.
The total potassium content Of an
acre of Illinois prairie soil to depth
| of eight inches is more than three
| times II 100 pounds. Thus, the COM
monest type of soil in the corn belt
| contains, in the first eight inches,
enough nitrogen for 60 years, enough
phosphorus for 80 years, and enough
| potassium for 1000 years if 100-bushel
crops of corn were the standard and if
| the stalks were all returned to the
| soil. If the entire crop including both
| grain and stalks, were removed from
| the land and nothing returned, then
the nitrogen would last 40 years, the
phosphorus 70 years, and the potas-
SUM 500 years.
| In 1904 the Illinois station harvest
| ed SO bushels of corn per acre from
| field which had been rotated in corn,
| oats and clover for % years. On an
| other adjoining field which had been
| in pasture for at least Is years pre-
vious to 1894 and in corn, oats and
clover since 1894, crop of "A bushels
| was produced without soil treatment;
! but where lime and phosphorus had
| been applied to a part of the same field
| Sc bushels per acre were produced.
The value of the % bushels increase is
not only double the annual cost of the
| limestone and bone meal applied, but
| the phosphorus applied is more than
would be removed in 100-bushel crop
of corn, so that this field is not only
| growing larger crops but at the same
time it is being made richer and rich
er year by year, whereas the untreat-
ed land which produced IA bushels per
acre is poorer by the IL pounds of
| phosphorus removed in the crop. The
| II pounds are more than 1 per cent.
| of the total phosphorus in the first
| eight inches.
If the phosphorus is continually sold
| from the farm in grain or in the
| bones of animals, it must also be
| brought back, either in corn, or in con-
| centrated feeds Gas bran or oil meaD,
| or in bone meal Originally a farm
| product), or in rock phosphate from
our great natural deposits, of which
more than million tons are now be-
| ing shipped annually from the United
| States to foreign countries.
Briefly stated, with the use of suf-
| ficient limestone to keep the soil
sweet and abundant, use of legume
crops and catch crops, and the addi-
| ton to the soil of ton of ground rock
| phosphate, or it's equivalent, every six
| or eight years, in connection with all
| of the farm manure which can be
made the ordinary lands of the Cen
trail West can be made to grow large
crops indefinitely"
Cyril G.. Hopkins.
University of Illinois.