140 ROOT DEVELOPMENT IN THE GRASSLAND FORMATION. 



possibilities present themselves. Chief among these are the compo- 

 sition of the soils and the moisture relations of the habitat. 



Mechanical analyses of the soils are given in table 17, together 

 with the moisture equivalents computed from the mechanical compo- 

 sition by the formula of Alway and Russel (1916:842). These data 

 show that both soils are fine-textured, being composed mostly of silt 

 and clay. A study of the table shows that they are remarkably similar. 



Table 18 gives the chemical composition of representative composite 

 samples of soil at various depths from the two areas. A study o»f the 

 table shows that the soils at the two stations are not strikingly different. 

 It should be noted that the lime content is about the same in both 

 fields. However, the greater amount of volatile matter and the greater 

 nitrogen content at all depths indicate more favorable conditions for 

 growth in the lowland plats, and this probably accounts in part for the 

 more rapid growth and better development of the crops in this field. 



Table 18.- 



-Chcmical analyses of soils by digestion with hydrochloric acid (sp. gr. 1.115) for 

 120 hours. 



