Voe. XI Washington, D. C., October 22, 1917 No. 4 
EFFECT OF SULPHUR ON DIFFERENT CROPS AND 
SOILS 1 
By O. M. Shedd, 2 
Chemist, Kentucky Agricultural Experiment Station 
INTRODUCTION 
There has recently been some discussion as to the importance and 
supply for plant growth of sulphur in its various compounds in soils, 
and whether or not it may be a limiting element in crop production. 
While it is one of the essential elements, the amounts found by the old 
method of ashing plants were so low in most cases that it was generally 
assumed there was an abundant supply of its compounds in soils for all 
crop requirements. More recently, however, it has been demonstrated 
by improved methods of analysis that most plants contain much more 
sulphur than was formerly thought to be the case, owing to the fact that 
in many instances by the old method the bulk of the sulphur was lost 
on ashing the plant, and therefore was overlooked. The question then 
arose as to whether there is an ample supply of sulphur compounds in 
soils for crop needs and especially for the best growth of those which are 
now known to have a high sulphur content. 
Hart and Peterson (4), 3 of Wisconsin, later the writer (5), and after¬ 
wards Brown and Kellogg (2), of Iowa, Ames and Boltz (1), of Ohio, 
and others have found that the sulphur content of many soils is low and 
that there has been a decided loss of sulphur in some soils which have 
been cultivated for a long term of years when compared with the cor¬ 
responding virgin soils. 
Some investigators contend that, although some soils are low in sul¬ 
phur, lower in many cases than in phosphorus, this is compensated for 
by the amount brought down in the rainfall; and as a result it will never 
be a limiting element in crop production. There are others, however, 
1 Approved for publication in the Journal of Agricultural Research by A. M. Peter. Acting Director, Ken¬ 
tucky Agricultural Experiment Station, July 25,1917. 
2 The writer desires to express his thanks to Dr. Peter, for his helpful suggestions in the preparation of 
the manuscript, and to the county agents who assisted in the collection of the soils. 
3 Reference is made by number to “ Literature cited,” p. 103. 
Journal of Agricultural Research, 
Vol. XI, No. 4 
Washington, D. C. 
Oct. 22,1917 
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(91) 
Key No. Ky.-~s 
