309 
THE CHEMICAL COMPOSITION OF VIRGIN AND CROPPED 
INDIANA SOILS. 
S. D. CONNER. 
In November, 1915, the Soils and Crops Department of the Purdue 
Agricultural Experiment Station collected samples of a large number of 
typical virgin and cropped soils, with a view to determine the chemical 
composition, to see if there was any appreciable difference in them. The 
samples were taken with an auger and each sample represented not less 
than five borings to a depth of six and one-half inches. Subsoil samples 
were taken at the same time and represented the layer from a depth of 12 
to 18 inches. Great care was taken to select fields where uniform and 
typical samples could be secured. The samples in each case represent a 
heavily cropped soil and an adjacent virgin soil of the same type which 
had never been cropped. The virgin soil samples were taken from a line 
fence row, or from a woodlot which had never been cultivated. The sepa- 
rate samples were properly prepared and analyzed for various elements. 
Also composite samples were prepared from the virgin soils, the virgin 
subsoils, the cropped soils and the cropped subsoils. The composites were 
made by taking equal weights of the separate samples and thoroughly mix- 
ing them. The analyses of the separate samples not being completed up 
to the present time, the analyses of the composite samples only are given 
in this paper. 
There is a rather widespread idea that the chemist can take a sample 
of soil and by making a complete analysis, determine without any other 
information just what element is deficient in the soil and needed as a 
fertilizer. This is not true, and it is very seldom that an analysis alone 
will indicate the needs of a soil. The chemist can tell with a fair degree 
of accuracy just how much of each element is present in the soil, but he is 
not able from a chemical analysis alone, to say what various crops are 
able to extract from the soil. The ability to determine the fertilizer needs 
of various crops on different types of soil is more or less a matter of 
