MESOPHYTES 



353 



In northern Illinois the upland forest is generally made 

 up of white and red oaks and shellbark hickory; while the 

 flood-plain forest contains twenty to twenty-five tree forms, 



FIG. 318. Junction between an upland forest (oaks on the slope t( 

 and a flood-plain forest (on the level ground to the left). 



ight) 



prominent among which are the elms (white and slippery), 

 linden (basswood), cotton wood, ash, silver maple, box-elder, 

 walnut, and willows (Fig. 318). 



Farther south, from central Illinois, Indiana, and Ohio 

 southward, as well as in the Alleghanies, the flood-plain 

 forests are the richest known, containing, in addition to 

 the forms enumerated above, such prominent trees as syca- 

 more, beech, sugar-maple, tulip-tree (white poplar), buck- 

 eye, hackberry, honey-locust, coffee-tree, etc. 



In Michigan and Wisconsin the upland forests consist 

 prominently of beech, sugar-maple, and hemlock, a char- 

 acteristic mixture of deciduous and evergreen trees; while 

 the flood-plain forests are scarcely at all developed. 



