POTASH IN MASSACHUSETTS SOILS 7 



forming processes have not yet effected any profound changes in the soil material. 

 One of these processes removes clay from the surface layer, carries it downward, 

 and deposits it in the layer beneath. The surface layer becomes coarser in texture, 

 while the underlying layer becomes finer. Six Worcester County soils of different 

 series showed no marked increase in clay at depths between 6 inches and 2 feet. 

 They are young soils because the changes which have taken place in the glacial 

 material are comparatively slight. 



Soils are never wholly dissolved in the solution of hydrochloric acid used in 

 these analyses. The proportion that is dissolved depends principally upon the 

 fineness of the soil particles. Clay will dissolve more freely than the finest sand. 

 In glacial soils, the clay was formed by the grinding action of the moving ice, 

 which reduced the softer minerals to rock flour. Feldspar, which contains potash, 

 is softer than quartz, which does not contain any. The finer the soil, the more 

 potash it may yield to any solution and clay may appear to be richer than sand. 



Numerous samples of soils from different levels were procured from the vicinity 

 of the College and analyzed by Frost, who also subjected them to a mechanical 

 analysis by separation into several graded sizes of soil particles. In the next 

 table are given the results of the mechanical analyses as well as the percentage 

 of potash in those samples. 



Table 2.~Potash and texture of soils at Massachusetts State College 



