Feb. II, 1918 Effect of Season and Crop Growth on Soil Extract 321 



may, if desired, be recalculated to the usual form. A study of these 

 figures shows that the members of each group of soils in physical texture 

 are as similar as was desired. From these analyses Mr. C. F. Shaw, of 

 this Station, states that the silty clay loams would be accurately classed 

 as — 



clay loams with a very high percentage of fine sand and silt, and that with the excep- 

 tion of No. 6 they would function as very tmiform silty clay loams. No. 6 would be 

 classed as a clay. 



The fine sandy loams are considered to be quite uniform in texture, so 

 far as porosity, ease of root penetration, and behavior under cultivation 

 are concerned. The moisture equivalents are very different, so that at 

 first glance it would appear that the plants would be unequally sup- 

 plied, especially in the fine sandy loams. It will be pointed out later, 

 however, that this view does not consider the fixed or "unfree" water 

 of the soil. The amount of moisture, therefore, which is available to the 

 plants, as shown by the wilting coefficient, and also the amount which 

 affects the concentration of the soil solution, can not be judged from 

 the moisture equivalent alone. 



Table II. — Moisture equivalents, hygroscopic coefficients, specific heat, and mechanical 

 analysis of experimental soils 



MOISTURE EQUIVALENTS 



