ANALYSES OF ONE HUNDRED SOILS IN ALLEN COUNTY, 
INDIANA. 
R. H. Carr and V. R. PHARES, Purdue University. 
The soils of Indiana present about as varied types and are as differ- 
ent in fertility as any that can be found. They include such famous 
areas as the sand dunes about Valparaiso, the peppermint fields of 
Mishawaka, and the limestone country about Bedford. There is quite a 
difference in soils not only between neighboring counties but even be- 
tween adjacent farms, differences which the casual observer seldom 
notices, because to him all soils look alike and are “just dirt.” 
CALLING THE “SOIL DOCTOR.” 
Soils are usually studied only after a series of failures of wheat, 
clover, etc., and the question naturally arises, “Why can I not grow 
crops like father used to?” It is at this stage of the soil’s depletion 
that the “soil doctor” is called often to prescribe for the sick soil. The 
ability of the doctor to diagnose the case through analysis has been 
overestimated somewhat in the popular mind. Nevertheless it usually 
gives the best answer as to why the wheat or clover failed to do well. 
Of all the soils investigated in this county by the writers, it was found 
that, where the physical conditions permitted, the crop yield was closely 
related to the amount of organic matter and plant food present, as shown 
in the graphs which follow. 
VALUE OF SOIL ANALYSIS. 
One reason for the questioning by many scientific men the value of 
analysis as a means of measuring fertility, is the varying results in 
pot and field work and the inability to correlate or interpret the results 
with the known composition of the soil. The conflicting results are 
often due to artificial surrounding conditions or to the use of seed of 
variable vitality, etc. Hence it was the purpose of this investigation to 
visit the growing plant, especially corn, in its natural home and there 
seek the reason of its good growth or the cause of its failure. 
PLAN OF INVESTIGATION. 
All the soils studied were secured in Allen County. They are of 
glacial origin, 70% belonging to the Miami series and 18.5% to the 
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