398 



Journal of Agricultural Research 



Vol. X, No. 8 



In eastern Nebraska we did not find such a low ratio in the first foot. 

 Throughout the season of 191 2 a field of bluegrass close to the Experi- 

 ment Station at Lincoln was kept under close observation, the surface 

 foot at frequent intervals being sampled in i inch sections. After two 

 or three weeks of dry, hot weather the ratio would fall as low as i.i to 

 1.3, but not lower (2, p. 59). 



Table V. — Ratio of moisture content to the hygroscopic coefficient in the different por- 

 tions of the surface foot of various fields in western Nebraska in the spring of igii 



CHARACTER OF THE SOILS USED 



Seventeen soils in all were used in the experiments, twelve of these being 

 identical with those described in a previous paper (2, p. 32). Twelve 

 were from Nebraska, two from New Mexico, one from Arizona, and two 

 from the southern end of the Colorado Desert in California. Instead of 

 being selected to cover the whole range in texture from clays to coarse 

 sands the Nebraska soils were intended to represent some of the most 

 important types in that State, while to each of those from other States 

 an unusual interest attaches because of their behavior in their natural 

 position in the field. 



Soils A, C, D, K, G, and H are silt loams from the loess; I, J, K, L, 

 and M are residual soils from western Nebraska; and O is a dune sand 

 from a "blow-out" in the Nebraska sand-hill region. 



Soil F, from Cuervo, in northeastern New Mexico, is a residual soil 

 derived from the red beds. In its natural position this soil offers such 

 great resistance to the downward movement of moisture that the water 

 from a heavy shower was found in small pools on the surface, while only 

 12 inches below the bottom of the pools 20 hours after the shower the 

 soil was still as dry as powder. Soil N is a red sand from Orogrande in 

 the Tularosa Desert in southern New Mexico; and N, a fine-textured 

 alluvial soil from near Douglas, Arizona, is typical of those deep soils of 

 the Southwest which fail to accumulate moisture through summer fallow- 

 ing. D is a subsoil from the abandoned Pope olive orchard described by 



