35 



A 75-YEAR OLD Stand, Raxdolph County 



The flatness of this section is varied by occasional preglacial emi- 

 nences and glacial moraines rising above the general level, and by stream 

 courses cut nuder this level surface. In such places drainage is good, and 

 the stands belong to the upland hardwood type found throughout the in- 

 terior in the central and northern parts of the state. 



On the moraines and like areas of the preglacial eminences where 

 the soils are deep, forest growth is the best for the uplands of the region. 

 Black oak is the commonest tree ; associated species are white and red 

 oak, hickory, ash, and cherry. These are the only upland areas within 

 this region where black walnut grows well. On those preglacial emi- 

 nences where the soils are thin, frequently a very inferior growth of scrub 

 oak {Q. marilandica) occurs. 



On the slopes where the flat upland breaks to the stream, the soil type 

 changes to yellow-gray silt loam and lacks the tight subsoil. These slopes 

 are among the best agricultural soils of the region. They were originally 

 entirely forested, but have been cleared in those areas where the slopes 

 permit tillage. Gully erosion was noted in Perry, Washington, William- 

 son, Franklin, Jefferson, Clay, Hamilton, and Wayne counties. In gen- 

 eral the steeper slopes are forested. White oak is often the commonest 

 tree. Shingle and black oaks together with white oak often comprise 90 

 per cent of the stand on the southern and the western exposures. Other 

 species are hickory, ash, basswood, cherry, hard maple, elm, and black 

 walnut. 



The virgin forest has long since been cut from the uplands, the suc- 

 ceeding growth is harvested as soon as the trees grow to small sawlog 

 size, and even the saplings are frequently worked into mine timbers ; yet 

 fire and grazing injury has not been common, the result being that the 

 remaining stands throughout this region are better stocked than those of 

 either the Ozark bluft" region or the upland hardwood region to the north. 

 Regeneration is by both sprouts and seedlings. The stands are uneven- 

 aged, with full representation from saplings to small sawlog size. 



(2) Scrub Oak 



Sands and sandy loams are found throughout central and northern 

 Illinois. Waters from the melting ice-sheets carried great quantities of 

 soils. The coarser materials, such as gravels and sands, were quickly 

 deposited. Receding floods exposed these deposits to wind action, and 

 the finer sands drifted. Whenever conditions became stabilized to the 



