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prevent overflow. Many projects of this nature are now in course 

 of execution. Only those portions that are most difficult of drainage 

 are suitable for reservation as permanent farm woodlots. Although 

 eventually all the overflow lands will doubtless be reclaimed, extensive 

 areas will probably remain unimproved for periods ranging from ten 

 to forty years, and in the meantime should be made to produce as much 

 timber as possible. 



The hill type of forest, since it grows on rough land, will, to a 

 large extent, be permanent. Steep slopes may not safely be cleared 

 because of the danger of erosion and the consequent destruction of the 

 value of the land for any purpose. The higher ridges are of no value 

 for raising agricultural crops, and would be better left in timber. The 

 chief perplexity that arises in connection with the determination of the 

 best use of this class of land is whether or not it should be devoted 

 primarily to stock-raising. It is not profitable to try to combine per- 

 manent timber production with heavy grazing. However, it is entirely 

 possible to graze a limited number of animals on forest land without 

 injury to the older trees, and to provide for the renewal of the forest 

 by keeping the stock off from sections that are being restocked with 

 young growth, until the trees are large enough to escape injury. This 

 will probably prove to be the most satisfactory policy in regard to most 

 of the hill forest land. The higher portions of this region are the only 

 parts of Illinois that contain absolute forest land in bodies more 

 extensive than ordinary farm woodlots. 



In the uplands of the lower Illinoisan glaciation, the black oak- 

 hickory type on broken land is most suitable for permanent woodlots. 

 The post-oak flats are not suited to growing timber of good quality, 

 and at the same time the rate of growth is very slow. Land of this 

 class is nevertheless considered worth from $20 to $40 — a price far 

 above its value for timber production. Although the soil is not 

 naturally fertile, experience has shown that in most cases it will 

 respond to proper treatment and in a few years will produce much 

 more in agricultural crops than in timber. This type of land, there- 

 fore, should be cleared as fast as needed, and the woodlots confined to 

 the portions with poorest drainage and to the black oak-hickory land, 

 where this is available. 



Practically all of the northern Illinois upland woodlots should 

 remain in forest, since the clearing off of timber has already gone 

 too far. It is especially important to maintain a forest cover on steep 

 slopes that are likely to wash out, and on very sandy soils that are 

 likely to blow. Examples of bad erosion following the clearing of 

 slopes that should have remained in timber are found in western Carroll 

 County south of Savanna. Unwise clearing ruins land both for 

 agriculture and timber production. 



