MARYLAND GEOLOGICAL SURVEY 307 



At present the greater part of the lumbering is in the Slope and 

 Swamp forests, but unless the ridge timber is also cut, most of the 

 mills will be idle in a few years. 



The character of the virgin forests may be best understood by a 

 study of them by types. The distribution of the types is shown on 

 the map (Plate XXI). 



Ridge Timber. 



This forest type occupies the benches and broken, rocky crests 

 (see Plate IX, Fig. 6 and Plate XXY, Fig. 1) of Backbone, 

 Meadow, and Negro mountains. It is essentially a chestnut for- 

 est. The soils upon which it occurs are shallow and sandy, or 

 very rocky. The acreage of this forest (20,220) is four times the 

 combined acreage of the other two types. Commercially it is the 

 least important of the three. This is due to the inferior character of 

 the Ridge Timber. The trees have short trunks, and are often stunted 

 in exposed situations. The Chestnut, which is the principal commer- 

 cial tree of the type, is usually defective. The trunks are first in- 

 jured by repeated fires, and finally rendered unfit for lumber by the 

 entrance of fungi and insects. The defectiveness of the Ridge 

 Timber is the principal reason for such large areas remaining unlum- 

 bered. It is probable that, with the exhaustion of the timber of the 

 Slope and Swamp forests, and the development of the mining inter- 

 ests of the county, the Ridge Timber will be lumbered and thus added 

 to the cut and culled area of the county. The character of this type, 

 in which Chestnut predominates, is shown in Table No. 1, on follow- 

 ing page. 



Slope Timber. 



The Slope Timber is commercially the most important of the three 

 types. It contains the largest number of species, and, with one 

 exception (Table No. 6), the heaviest growth of timber. The compo- 

 sition of the slope forest varies between two extremes. On the steep 

 slopes above the Youghiogheny river it is often pure Hemlock, and 

 in the richer coves almost pure White Oak. Between these extremes 

 we have slopes upon which Hemlock and hardwoods mingle, while 



