Hopkins, Cyril G.

Pettit, James H.

Readhimer, J.E.

Illinois Digital Environment for Access to Learning and Scholarship Repository

Reference tile 
icuh. urtA.l Li l''Y 
UNIVERSITY OF ILLINOIS 
Agricultural Experiment Station 
URBANA, OCTOBER, 1905 
CIRCULAR NO. 100 
THE "GIST" OF FOUR YEARS' SOIL INVESTIGATION IN 
THE ILLINOIS CORN BELT. 
BY CYRIL G. HoPKINs , CHIEF IN AGRONOMY, J. H . PETTIT, FIRST AssisT-
ANT IN SoiL FERTILITY, AND J. E. READHIMER, SuPERINTENDENT oF 
SoiL ExPERIMENT FIELDS. 
Nitrogen. 
At ordinary commercial prices the nitrogen contained in the air 
above each acre is worth more than ten million dollars. B y means of 
bacteria which live on their roots, clover and other legumes have power 
to draw on this unlimited supply of free nitrogen. 
Potassium. 
The or.dinary, naturally well surface-drained land of the Corn Belt 
in Central and Northern Illinois c9ntains in the soil of one acre to a depth 
of seven inches sufficient total potassium for a hundred 6ushels of corn 
each year for 1900 years , if the stalks are returned to the land directly 
or in manure. The supply is about 36,000 pounds and one hundred 
bushels of corn (grain only) contain 19 pounds of potassium. Potassium 
may be liberated from the soil as needed, by means of decaying ,.,organic 
matter, such as farm manure, clover residues , and legume catch crops as 
green manures. 
2 
TABLE L CROP YIELDS IN SoiL ExPERIMENTS : BLooMINGTON FIELD: 
CoMMERCIAL NITROGEN SERIES. 
Typical Corn Belt Soil: Brown Silt Loam Prairie of the Early Wisconsin 
Glaciation. 
1902 1903 1904 1905 
Plant Food Applied. Corn, Corn, Oats, Wheat, 
bu. bu. bu. bu. 
-
None . ... .. ....... . ..... ... .. . . .. .. . . . . 37 60 61 29 
Nitrogen . . . . .......... . ............... 35 60 70 31 
Phosphorus ..... . ................. . .... 42 73 73 39 
Potassium . ....... . . . ...... . . .... . ... .. 38 56 63 33 
Nitrogen, phosphorus •• • •••• 0 •• • ••• • • ••• 44 78 85 51 
Nitrogen, potassium ........... . ... ; .. . . 40 59 66 30 
Phosphorus, potassium . ... ... ......... .. . so 75 70 38 
Nitrogen, phosphorus, potassium •• • • •• 0 0. 53 81 91 52 
Average gain for nitrogen ...... .. ... . ... . 1 4 11 6 
Average gain for Phospho~us . ..... . ... .. 10 18 15 14 
Average gain for potassium .............. 6* 0 0 1 
,. 1- ------
Average gain for phosphorus when 
added to nitrogen ......... . .. ... .... 11 20 20 21 
Value of this increase •••• •• •••• •• 0 • • •••• $-3.85 $7.00 $5.00 $14.70 
Approximate Cost of 2 5 Pounds of Phosphorus. 
In rock phosphate . . ............ . ... . .... . . ...... $ . 80 
In steamed bone meal. . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 . 50 
In acid phosphate . .. . ........ : .· . . . . .. .. ... ...... 3 . 20 
In ''complete fertilizer '' . . . . . . . . . . . . . . . . . . . . . . . . . . 8. 00 
*Potassium is applied as a soluble, corrosive salt which, like common salt, sometimes 
a cts as a stimulant and thus liberates some phosphorus or nitrogen from the soil. 
3 
TABLE 2. CRoP YIELDS JN So iL ExPERIMENTs: U:RBANA FIELD : THREE-
YEAR R oTATION: LEGUME SERIES . 
Typical Corn Belt Soil : Brown Silt Loam Prairie of the Early Wisconsin 
Glaciation. 
Corn. Oats. Clover. 
·Soil treatment applied. 3 yr . av., 2 yr~ av. , 2 yr. av., 
bu. bu. tons. 
None . . .. . . . .. . . . . . . . 77 48 1 . 65 
Legume (catch crops) •• • • • • 0 . . ... . . 77 51 1 . 69 
Legume, lime .... . . . . . ... . . . . 78 56 1. 70 
Legume, lime, phosphorus* . . .. . . . . . 89 67 2 .47 
Legume, lime, phosphorus, potassium 91 68 2 .82 
Gain for legume ...... . . . . . . . . . . . . . . . 0 3 . 04 
Gain for lime • • • 0 . .... . . . . . . . . . 5 .01 
Gain for phosphorus . . .. . ...... . . . . 11 11 . 77 
Gain for potassium . . . . . . . ... . . . . . . 2 . 35 
Value of Increase and Cost of Treatment . 
Corn. Oats. Clover. Total for Cost for 
3 years. 3 years. 
For legume . ..... . ...... .. . $ . 00 $ . 75 $ . 20 $ . 95 $ ( ?) 
For lime . ......... ... ...... .35 1 . 25 .05 1. 65 1. 50 
For phosphorus ........ . .... 3 . 85 2 . 75 3 . 85 10.45 7 . 50* 
For potassium ... ........ . .. . 70 . 25 1 . 75 2 . 70 7 . 50t 
- -
*$7. 50 supplies 7 5 pounds of phosphorus in steamed bone m eal. The three crops have 
removed only 43 pounds of phosphorus. 
t$7 .50 supplies 120 pounds of potassium. The three crops have r emoved 194 pounds 
of potassium. 
NoTE.-On the field where a catch crop of clover was seeded in t he com in 1902 oats 
and clover were seeded in 1903 by "dis king in," without plowing; but the old clover still 
grew and smothered out the oats and the young clover. Hence we give t he average of 
only two years' results from oats and clover with three years' from com. 
Agricultural Libra1 .. y 
4 
Phosphoru~. 
If we could draw at will upon the total phosphorus in the first seven 
inches of soil the supply (about 1200 pounds) would be entire!y exh9-usted 
to that depth d~ring the lifetime of one man, if hundred-bushel crops of 
com were taken from the land. A hundred-bushel crop of corn requires 
seventeen pounds of phosphorus for the grain and six pounds for the 
stalks. Oats, wheat, and clover also draw heavily upon phosphorus. 
When crops are fed the animals store in their bones about one-fourth of 
the phosphorus contained in the food consumed. 
By means of decaying organic matter we can liberate each year a 
small percentage of the phosphorus in the soil. If we need more than·. 
we can profitably liberate from the soil, we should apply it in the cheap-
est and most natural form, preferably as steamed bone meal or as finely 
ground raw rock phosphate in connection with manure or clover. Steamed· 
bone meal is really a farm product and raw rock phosphate is a natural 
plant food material, and neither will ever injure the soil. The use of 
acidulated manufactured fertilizers is not advised. 
Results . 
On the Bloomington experiment field for the three years, 1903, 1904, 
and 1905, we applied, in all, 300 pounds per acre of commercial nitrogen 
at 16 cents a pound, 75 pounds of phosphorus at 10 cents a pound, and 
120 pounds of potassium at 61 cents a p~und. We removed from the best 
yielding plot, in the three crops, com, oats, and wheat, 287 pounds of 
nitrogen , 45 pounds of phosphorus and 176 pounds of potassium, per acre. 
Measured by the crop yields, we have gained (on the best yielding plot) 
13 pounds of nitrogen and lost (as an average of four plots) $39.65 of 
the $48 invested in dried blood; we have gained 30 pounds of phosphorus 
and have also gained $12.35 in money above the $7.50 invested in steamed 
bone meal; and we have lost 56 pounds of potassium more than we applied 
and we have also lost $6.80 of the $7.50 invested in potassium. 
For more detailed information regarding methods of soil improve-
ment, cost and methods of applying plant food materials, comparative 
value of steamed bone meal and raw rock phosphate, systems of crop 
rotations, the use of legume catch crops, etc., see Circulars 87, 96, and 97, 
which will be sent free of charge upon request. 
Any one interested in Illinois Agriculture can have his name placed 
· upon the permanent free mailing list for all circulars and bulletins, upon 
his own request, which should be made by letter or postal card addressed 
AGRICULTURAL ExPERIME T STATIO , 
Urbana, Ill. 


The "gist" of four years' soil investigation in the Illinois corn belt

IDEALS @ Illinois

https://www.ideals.illinois.edu/bitstream/handle/2142/33117/1132514.pdf?sequence=2

The "gist" of four years' soil investigation in the Illinois corn belt

Abstract

Similar works

Full text

Available Versions

Illinois Digital Environment for Access to Learning and Scholarship Repository

IDEALS @ Illinois