Pool: THE VEGETATION OF THE SANDHILLS OF NEBRASKA 199 



are usually not continuous for long distances, unless such a valley be 

 the position of a stream. Meadows and valleys are frequently com- 

 pletely enclosed by ranges of hills and in this way effectively sepa- 

 rated from adjacent valleys although such may not be more than a 

 half-mile distant over a low saddle or ridge. In other cases adjacent 

 valleys are united by their ends or sides so that in some parts of the 

 region one may travel for many miles over the firm soil of the val- 

 ley floor by simply angling from one valley around a spur or end of 

 a range of hills into another valley. High spurlike promon- 

 tories often extend from the main range of hills into the val- 

 leys from the sides. This condition results in the production of a 

 very irregular boundary line for many valleys. Oftentimes the sides 

 of the hills or ridges are very steep, thus making difficult, or nearly 

 impossible in some instances, the direct lateral passage from one 

 lowland area to another. Where broad valleys are the rule, the 

 ranges of hills often reveal a succession of higher hills as one passes 

 back from the valley to the highest points on the divide. This di- 

 vide may be as high as 100 to 250 feet above the valley floor. Along 

 the northeastern limits of the region low, tortuous ranges of hills 

 separate broad, fertile meadow lands whose soil when "broken" 

 yields abundantly of various field and cultivated forage crops. But 

 in those portions of the hills characterized by very short dry val- 

 leys and basins the general topographic conditions are strikingly 

 different because in such places the hills rise on all sides without 

 the customary regularity of distribution into lengthy ranges. Even 

 the general typical east and west trend of the hills is difficult to 

 discern in many such places. Low hills, intermediate hills, and 

 high hills are closely associated in every direction and there are con- 

 sequently no prominent dissecting valleys. The result of this type of 

 hill distribution is the production of a very abruptly rolling surface 

 with considerable relief consisting of short, oblong, or rounded de- 

 pressions of varying depth with the rounded or conical dunes above. 

 Such hills frequently bear many of the characteristic blow-outs. The 

 highest hills are usually of a nearly uniform altitude but occasionally 

 one sees a giant hill that towers above the others to such a degree 

 that it has received a local name such as "Plummer's hill" on the 

 Dismal or "Cowboy hill" in Morrill County. The ranchman desig- 

 nates this condition as "choppy hills." There are places where this 

 sort of topography stretches in all directions as far as one can see. 

 The general altitude above sea level of the sandhill region varies 



