Ecology of the Cincinnati Region 
177 
forest of the upland, is this forest, which will be termed the erosion 
climax. 
IV. TERRACES AND FILLED VALLEYS 
Combining, in a measure, the features of uplands and of slopes, of 
pre-erosion and erosion vegetational types, is a topographic division of 
great prominence, and a vegetation series of somewhat intermediate 
character. The flats of abandoned river valleys and the younger glacial 
terraces of present streams have not been greatly modifled by the forces 
of erosion. Older terrace remnants are much dissected, and their vegeta¬ 
tion belongs more properly to the slope series. 
The terraces and pre-glacial valleys of the region show less of their 
original vegetation than any other equal area in the region under con¬ 
sideration, for they are very favorably situated for both agricultural and 
commercial pursuits. The discussion is necessarily based on isolated 
and sometimes poorly preserved remnants. 
Terrace associations may be grouped into two classes, the associa¬ 
tions of gravel terraces, and the associations of sand and silt terraces, 
each dependent on the physical character of the terrace material. Between 
these two classes, there are a number of intermediate forms for the ter¬ 
race materials intergrade. 
A. GRAVEL TERRACES 
Gravel terraces are limited to a few small areas. Most of these lie 
along the Miami and Little Miami rivers. Because of their very favor¬ 
able situation above the reach of floods, and their nearly level surface, 
the terraces have been cleared for many years, and it is only in a few 
spots that any of their original vegetation remains. 
1. Forest associations 
A few large trees remain upon the terraces. These are usually 
beech, but here and there is an occasional wild black cherry or sugar 
maple. From these few remnants it would appear, that the original 
forest of the gravel terrace was dominated by beech, and probably resem¬ 
bled the beech forest of the upland. Near the top of river bluffs or of 
ravines in the terrace, the mesophytic forest is replaced by one resembling 
the forests of the margins of uplands!' Red oak, white oak, chestnut 
oak, and sometimes red cedar replace the mesophytes of the level terrace. 
