a minimum of 2,000 board feet up to 18,000. Because 

 of the wide range in volume per acre, these areas 

 have been further classified as follows: 



Board feet per acre: Acres 



8,000 or more 24, 500 



6,000 to 7,999 24, 700 



4,000 to 5,999 40, 100 



2,000 to 3,999 88, 100 



Total 177.400 



180 



160 



£ 140 



Q 



m 120 



2 

 O 



-: 100 



5 80 



UJ 



5 60 

 g 40 



20 

 



10 12 14 16 18 20 22 and up 



DIAMETER CLASS 

 (inches) 



Figure 24. — Diameter-class distribution of board-foot volume in 

 merchantable saw-timber stands. 



Major Forest Types 



Seven principal forest types are found in the forests 

 of the Anthracite Forest Region (tables 3 and 4). 



^"^ ■ c£*& z? 1 ^ Sugar Maple-Beech-Yellow Birch 



\ ^. * ^- The sugar maple-beech-yellow birch type is more 



important than any other in the Anthracite Region. 

 It is found only in the northern counties where it 

 f-<47493 dominates the highlands, largely at elevations of 



Figure 23.— Some saw-timber stands have escaped intensive utilization. about 1,200 feet. The principal species that com- 

 prise this type are beech, sugar maple, red maple, 

 The rapid growth of conifers and the location of and yellow birch, with associates of white ash, black 

 the merchantable saw-timber stands in the sugar cherry, and basswood. There is considerable hem- 

 maple-beech-yellow birch and white pine-hemlock lock in the moist ravines. Nearly half the saw timber 

 forest types are reflected in the proportional compo- and more than half the smaller material of the region 

 sition of saw timber by species: is in this type. The saw-timber stands average about 



Percent 4,500 board feet per acre and the pole-timber stands 



Hemlock 19 about 20 tons. The species in this type grow fast and 



Beech 1 1 ~1 



„ , ' respond well to selective cutting. Fires in woods of 



White pine. 12 ^is type are not common. In clear-cut areas, how- 

 Hard maple 9 ever, fire may hinder reproduction and allow the 



Red maple g invasion of aspen, gray birch, and pin cherry. This 



Other hardwoods .... 1 8 has happened in parts of the North Mountain section 



and in the highlands east of the Wyoming Valley. 

 More than a quarter of the board-foot volume in 

 merchantable saw-timber stands is in trees 19.0 Aspen-Gray Birch-Pin Cherry 



inches and larger (fig. 24), but there are very few Stands of trembling aspen, gray birch, and pin 



trees that exceed 30 inches. cherry with a few remnants of red maple, black cherry, 



22 Miscellaneous Publication 648, U. S. Department of Agriculture 



