THE VEGETATION OF CONGLOMERATE ROCKS OF 

 THE CINCINNATI REGION 



E. LUCY BRAUN 



University of Cincinnati, Cincinnati, Ohio 



On the limited areas of conglomerate rock within the Cin- 

 cinnati region, is a vegetation so unique for this region, so dif- 

 ferent from all the surrounding vegetation, that it has no place 

 in the major plant formations of the region. On these rocks 

 there is an independent succession in progress which only in its 

 latest stages, begins to merge with the surrounding associations. 



Location and extent of rock outcrop. Conglomerate rocks in 

 the Cincinnati region are exposed mostly in the little Miami 

 valley, and in that part of the Ohio valley just above the mouth 

 of the Little Miami river. A few areas also are found in the 

 Miami valley. The outcrops occur in groups, so that there 

 is usually a number of outcrops very close together. These 

 groups or areas may be several miles apart. Rock exposures 

 vary from a few square feet to hundreds of square feet in area. 

 All the outcrops are found on hillsides where there are remnants 

 of glacial terraces. 



Origin of the conglomerate. The conglomerate was made by 

 the cementation of outwash gravels of the Illinoian and Earlier 

 Wisconsin glacial stages. In most of the Cincinnati region, 

 these gravels — especially those of Wisconsin age — are loose 

 and unconsolidated, or only partially cemented. In places 

 they have been so well cemented as to form a very firm and 

 resistant conglomerate. 



Composition and texture. The pebbles and bowlders of the 

 conglomerates are of various materials — limestone, quartz, 

 and igneous rocks. Limestone everywhere predominates so 

 that the rock may be considered a limestone conglomerate. 

 The cement is calcareous, locally ferruginous. The texture of 



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