90 BOTANICAL GAZETTE [februaky 



Reimer and Tartar (58) conducted field experiments on sev- 

 eral Oregon soils. Superphosphate, flowers of sulphur, rock phos- 

 phate, potassium chloride, potassium sulphate, iron sulphate, 

 gypsum, monocalcium phosphate, sodium nitrate, ammonium 

 sulphate, magnesium sulphate, sodium sulphate, iron pyrites, 

 quick lime, and ground hmestone were used as fertiUzers. In 

 almost every case enormous increases in yields (from two to ten 

 times as much as the checks) were obtained for all the fertilizers 

 containing sulphur, and no increase or only a small increase 

 for the fertilizers which contained no sulphur. Acid phosphate 

 was compared with gypsum and rock phosphate and with rock 

 phosphate and flowers of sulphur. The yield on the plot receiving 

 rock phosphate and gypsum was considerably greater, and that 

 from the plot receiving rock phosphate and flowers of sulphur 

 slightly greater, than the yield from the acid phosphate treated 

 plot. The alfalfa on all the plots receiving sulphur in any form 

 was a darker green than on the plots which received no sulphur. 



Chemical analyses of soil samples from these experimental 

 fields were made. The sulphur content varied from 0.015 to 

 0.038 per cent in the surface soil, and from 0.014 to 0.030 per cent 

 in the subsoil. The phosphorus content varied from 0.048 to 

 0.076 per cent in the surface, and from 0.066 to 0.085 per cent in 

 the subsoil. All were high in calcium, magnesium, and potassium. 



Investigation 



The analyses made by Robinson (59, 60) show wide variation 

 in the sulphur content of different soil types. His investigations, 

 although extensive, have included only a part of the numerous soil 

 types found in the United States, so that other soil types should be 

 analyzed to discover their sulphur as well as their phosphorus 

 content. It is also necessary to conduct field experiments on the ' 

 different soils, as analytical data alone are not sufficient evidence 

 on which to base fertilizer practice. This investigation includes 

 soil analyses and field experiments. Soil samples from Indiana, 

 Kentucky, Michigan, Ohio, and Wisconsin were analyzed for 

 phosphorus, sulphur, and volatile matter (loss on ignition). Field 



