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one general forest association and a number of minor ones 



that may be designated as follows : 



a. The scarlet and white oak, a general forest growth. 



b. The aspen-poplar. 



c. The red elm-walnut. 



d. The white elm-willow. 



e. The black oak. 



f. The bur oak. 



g. Pine red cedar. 



The scarlet and zi'hite oak association is the all pervading 

 one and everywhere gives the general tone to the woodlands. 

 The association consists almost entirely of the oaks named, but 

 varies in every possible degree between a pure white oak and 

 a pure scarlet oak growth. In general, however, there will 

 be a small pref)onderance of one or the other species accord- 

 ing as the soil has .more or less humus and less or more clay. 

 The richer the soil, the more the scarlet oak abounds, and the 

 poorer and more clayey, the more abundant will be the 

 white oaks ; most of the trees of this association are second 

 growth ; a typical example, extending over one-half mile square, 

 having a tree for every five or ten feet square of land sur- 

 face, or 400 to 1600 to the acre. These trees will average 12 

 to 16 inches in diameter, 50 to 70 feet in height, and represent 

 a time growth for the scarlet oaks of 50 years, and for the 

 white oaks 75. Here and there large white oaks are to be 

 seen, two to four feet in diameter and up to 300 years of age. 

 Many such are suitable for sawmill material, but their num- 

 ber is very rapidly diminishing. Occasional scarlet oaks 2 feet 

 to 30 inches in diameter are found, of a probable age of a 

 century or more. Often there are absolutely no other tree 

 species included, and this will certainly be the case where the 

 soil is of moderate fertility. As the soil thins, the white oaks 

 with an occasional shag bark hickory presents a solid front. 

 Running to the other extreme of soil richness, there will be 

 found a few specimens of black cherry, pig-nut hickory, red 

 oak and very rarely a red elm and bass wood. 



As this exclusive association constitutes most of the forest 



