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UPLAND HILL TYPE 



The Ozark Hills region of southern Illinois, an extension of the 

 Ozark Plateau, lies in the angle formed by the Ohio and Mississippi 

 rivers, and is bounded on three sides by bottomlands. On the north, 

 these highlands rise from the undulating upland plain, sometimes 

 abruptly, sometimes gradually. In addition to these unglaciated hills, 

 there is a narrow strip of rough country along the Mississippi River 

 with similar topographic features and forest growth. The east 

 boundary of these bluff lands is not distinct, as the topography becomes 

 less broken in character eastward until it merges into the upland 

 plains. The line which marks this east boundary is drawn somewhat 

 arbitrarily on the map, and separates off a strip of hilly country three 

 to seven miles wide. 



In general the forests are confined to the slopes, since the ridges 

 and creek bottoms are usually under cultivation. However, there 

 are sections of very rough land in eastern Alexander, Union, and 

 Jackson counties, and in northern Pope and Hardin, that are almost 

 completely wooded. Here the ridges are sharp and narrow, with 

 numerous spurs, interlaced with a maze of steep-sided valleys. While 

 the underlying rock seldom outcrops in large exposures, these higher 

 ridges are often carpeted with small stones. Ordinarily, too, timber 

 grows in the sink-holes that characterize the limestone section of 

 Randolph and Monroe counties, back of the bluff line, and of Hardin 

 County, northeast of Cave-In-Rock. 



The forests of these two hill sections cover from twelve to thirty- 

 five per cent of the surface. They differ from those of the more 

 level uplands, not so much in the identity and proportion of the prin- 

 cipal species as in the greater variety of minor species and the better 

 development of the timber. The oaks and hickories together pre- 

 dominate, and form, respectively, about sixty and ten per cent of the 

 stand. In the southern counties on the Ohio and Mississippi rivers 

 (Pulaski, Alexander, Union, and Jackson), beech constitutes from 

 fourteen to thirty-eight per cent of the forest, but is rare elsewhere. 

 It grows in cool hollows and on north and east slopes. Black, Spanish. 

 red, white, post, and chinquapin are the principal oaks, but scarlet and 

 blackjack also characterize the stands. Pignut, mockernut, and shag- 

 bark are the chief hickories. Other characteristic trees are butternut, 

 black walnut, elm, mulberry, cucumber, tulip-poplar, red gum, black 

 cherry, coffeetree, black locust, sugar and silver maple, black gum, 

 and ash. The typical trees of the southern bottomlands grow on the 

 moist lower slopes and along the creeks. The richer slopes support 

 a mixture of white oak, red oak, tulip, cucumber, and nearly all the 

 trees of the region; while drier situations, such as upper slopes and 



