SULPHUR CONTENT OF SOILS AND ITS RELATION TO 
PLANT NUTRITION 
CONTRIBUTIONS FROM THE HULL BOTANICAL LABORATORY 297 
Scott V. EATON 
( ITH ONE FIGURE) 
Introduction 
Ever since the ten essential elements for plant nutrition were 
established by the work of Sacus, BousstncAuLt, Nopse, and 
other investigators, sulphur has been recognized as one of them. 
The ash analysis method of determining sulphur in plants, however, 
which was in use during this early period, showed such a small 
amount present that the needs of the plant were thought to be 
amply taken care of by the supply in the soil. Contributions 
during the last twenty years by BERTHELOT, BARLOW, FRAPS, 
Goss, BESTLE, SHERMAN, and others have shown that in ashing 
plant material much of the sulphur may be lost. The amount 
of sulphur in plants as determined by analyzing the ash may be 
only a fraction of the real amount. Thus the whole question of 
the relation of sulphur to plant nutrition has been reopened, 
for if plants use several times as much sulphur as had been sup- 
posed, then perhaps the supply in the soil is not sufficient for 
the needs of the plant. Recently there have been a number of 
contributions to the subject. The first questions to be considered 
have naturally been how much sulphur do crops use and what are 
the supplies to meet these needs. Thus the first problems to be 
investigated have been the sulphur content of crops, the sulphur 
content of soils, the amount of sulphur brought down by the rain, 
and the amount lost by drainage, etc. Next, sulphur was added 
to soils found to be low in it to see whether the yield of crops would 
be increased. In the present paper no attempt is made even to 
approximate a resumé of the sulphur literature, rather complete 
digests of which may be found in papers by CrockER (4) and 
OLSON (19). 
Botanical Gazette, vol. 74] [32 
