1 10 ROOT DEVELOPMENT IN THE GRASSLAND FORMATION. 



but also by the appearance of Stipa comata, Agwpyrum glaucwn, and 

 Liatris punctata. 



A field of rye about 3 miles northwest of Flagler was examined on 

 August 5, and about 3 weeks after it had been harvested. The crop 

 had grown on land broken out for 25 years. Following a crop of wheat, 

 the rye had been drilled the first week of September, after disking the 

 wheat stubble, at the rate of 30 pounds per acre. It came up well in the 

 fall, and although somewhat thin of stand, promised a good yield. 

 During the blossoming period, about the first of June, freezing weather, 

 accompanied by snow, cut the yield to only 10 bushels per acre. The 

 plants had an average height, when ripe, of about 2.1 feet. The soil 

 was of the usual chocolate-colored silt-loam type, and somewhat 

 columnar in structure, to a depth of 2.5 feet, where a grayish "hardpan" 

 0.7 to 0.9 foot in thickness was in evidence. Soils of arid regions are 

 uniformly high in their percentage of lime and usually also of magnesia, 

 and this quite independently of the underlying formations being cal- 

 careous or otherwise (Hilgard, 1911:374). Alway (1916:414) states 

 that in western Nebraska areas the carbonates, which are practically 

 absent from the first foot or two of soil, are distributed throughout the 

 subsoil mass instead of being segregated in the form of concretions, as 

 is characteristic in more humid areas. Frequently they constitute 3 to 

 6 per cent of the weight of the soil (Alway, 1919). Below this harder 

 layer the soil became lighter in color, dry, and very mellow. Below 

 1 foot it was uniformly moist to the working depth of the roots, which 

 occurred at 2.3 feet. The roots were very abundant to this depth, very 

 few extending deeper, although some were found to penetrate to 2.8 feet. 



Red spring wheat was examined in a field only a few rods away on 

 old land previously cropped with corn. The wheat had been disked late 

 in March at the rate of about 45 pounds per acre. This resulted in a 

 fairly thick stand. The crop reached an average height of 2.5 feet. The 

 only difference in soil structure was the depth of the "hardpan"; here 

 it occurred somewhat nearer the surface (at 2.3 feet). This shallower 

 depth may have been due to surface-soil blowing, for great ridges of 

 wind-blown silt had half buried the wire fence between the two fields. 

 The roots reached a working depth which corresponded to the depth of 

 moist soil (about 2.5 feet), only a very few extending 3 or 4 inches 

 deeper. 



About a mile eastward, a field of Yellow Kherson oats was examined 

 on land that had been broken for over 5 years. It was drilled on 

 April 2, following a crop of corn, the land having been plowed to a depth 

 of 0.5 foot. The silt-loam was very hard and dry near the surface, 

 while at 1.6 feet in depth a "hardpan" was encountered, below which 

 dry soil again occurred. Aside from cropping effects, the water-content 

 of the soil, even in adjacent level fields, is frequently considerably 

 varied by greater or less accumulations and subsequent melting of 



