The daily Gate City and constitution-Democrat. (Keokuk, Iowa) 1916-1922, 1916-06-20
\ Held at the State Experiment Station
Field In Carthage, With County
Agent J. n. Lloyd in
Charge.
MAKE CROP COMPARISON
Carthage Dentists Visit Hamilton to
Attend seni-Annuai Meeting Of
Adams-hanooo< Denta,
Society.

CARTHAGE, Illinois, June 90
The field meeting held at the state
experiment. station field at Carthage
on June 10th, was decided success,
County Agent ]. II. Lloyd had the
plans all completed for the meeting,
and the afternoon being favorable,
things went of according to schedule.
Dr. Cyril g. Hopkins, head of the
agronony department of the Univer-
sity OF Illinois. being present. "The
Illinois System Of Permanent Fertfli-
ty" being his subject. There were
more than two hundred farmers from
all parts of the county who gathered
on the experiment field. After a pre
liminary survey Of crops growing in
5 the field. Doctor Hopkins explained
the plan OF the experiments and gave
summary OF results secured, compar-
ing them with facts of similar fields
in other parts OF the country.
The field proper Is divided into four
equal plots each Of which is again
subdivided into ten parts making
forty plots In all -Four different
crops are grown each year, namely:
Wheat, corn, oats and clover, which
are rotated In the order named. Each
crop being grown but one year on
zach plot. The ten divisions Of each
Of the four plots are for the purpose
of testing different methods of soil
treatment. Plots /, s and 10 are
check plots and received no treat
ment. Plots @, 3 and represent the
live stock system Of farming, and re-
ceived the following application:
Plot 2. manure; plot 3, manure and
limestone; plot 4, manure, limestone
and phosphorus. The amount of man
ure applied equals by weight the
amount of crops removed.
Plots 6, Z, and 9 represent the
grain farming system. OF these, plot
6 has the crop residues, namely:
Straw, corn stalks, etc, returned to
the land together with a leguminous
crop consisting OF sweet clover and
alsike clover turned under with the
wheat stubble for corn. Plot Z has
the residue, legume crop and lime
stone. Plot 8 has residues, legume
crop. limestone and phosphorus, and
plot 8 has residues, legume crop.
limestone, phosphorus and potassium.
The full treatment was not applied
TO all plots until 1915. The treatment
is regularly applied to one series Of
plots one year, to another the second
year, and SO on around, and the COM
plete treatment was begun with the
series which grew corn in 1912, so
that they now have four years results
with corn grown upon series receiving
the full treatment, and also complete
data concerning the four corn crops.
The results secured during the
first rotation must in any case be re-
garded as largely preliminary, and
normally the differences become more
marked in subsequent rotations. be-
cause the soil receiving no enrich
ment or only partial treatment, such
as farm manure alone, tends to be-
come less productive, the manure pro
duced from the crops grown upon the
farm not being sufficient to maintain
the fertility of the soil, while the per-
manent system of soil treatment are
cumulative in effect, at least for
considerable number of years.
The application of manure is based
directly upon the amount which can
be produced from the crops grown.
The initial application Of limestone
is four tons per acre, but subsequent
applications are two tons per acre
once in four years. Rock phosphate