276 THE PLANT LIFE OF MARYLAND 



Maple (Acer pennsylvanicum) , the Mountain Ash (Sorbus ameri- 

 cana), the Yew (Taxus minor), the Flame Azalea (Azalea lutea), 

 the Hobble-hush (Viburnum alnifolium), and others. Among the 

 species of the Midland Zone which are absent are several trees abun- 

 dant in flood plains and on the banks of streams, as the Buttonwood 

 (Plat anus occidentalis), the Silver Maple (Acer saccharinum), the 

 American Elm (Ulmus americana) and others. 



A few small tracts of virgin forest have been spared in the Moun- 

 tain Zone, and so recent has been the clearing of the larger areas that 

 something may be learned by hearsay of the character and com- 

 position of their stands of merchantable trees. Even in the present 

 condition of the forests it is possible to detect differences in occur- 

 rence and distribution of the tree species due primarily to the topo- 

 graphic factors, and in a less degree to the influence of soil texture. 



Curran* has investigated the forests of Garrett County, and recog- 

 nized four major types of forest, the Ridge, Slope culled and cut- 

 over and Swamp types, the distribution of which he has indicated by 

 means of a map. The Ridge and Swamp types are designated here 

 by the same names, the Slope type is distinguished as the Rocky 

 Slope type. 



Of the seven forest types which will be described in this paper the 

 one which would be considered the highest from the standpoint of 

 physiographic ecology is that which occupies the lower slopes of the 

 main mountain ridges and the smaller hills. It is found throughout 

 the district and in the virgin state of the country was one of the 

 commonest types. The presence of a deep soil with an abundant 

 accumulation of humus material, added to conditions of soil mois- 

 ture which approach the optimum for forest trees, makes the Slope 

 habitat rich in tree species, all of which are deciduous, and particu- 

 larly rich in its herbaceous flora. 



The Ridges are much poorer in species of trees and in herbaceous 

 vegetation than the Slopes, having a stand made up chiefly of the 

 Chestnut (Castanea dentata) and Chestnut Oak (Quercus prinus). 

 The type reaches its greatest distinctness on the summits of Big 

 Savage, Great Backbone and Meadow mountains. The writer has 



*Curran, H. M. The Forests of Garrett County. Maryland Geological 

 Survey, Garrett County, 1904, pp. 303-329. 



