THE SPRUCE REGION 205 



forest types) revert to some one of the other four forest types 

 (permanent forest types). 



The six types are: 



Permanent Forest Types: 



1. Swamp. 



2. Spruce Flat. 



3. Hardwood. 



4. Spruce Slope. 



Temporary Forest Types: 



5. Birch and Poplar. 



6. Old Field. 



I. Sivamp. — Forests of the swamp type, as the name would 

 imply, occur on the low, wet ground near lakes and streams, and 

 are most abundant in the Maine section of the region. In Ver- 

 mont and the White Mountain section of New Hampshire rela- 

 tively little swamp land is found. 



The soil is apt to be wet throughout the year and is covered 

 with a dense bed of sphagnum moss often of considerable depth. 

 In certain times of the year the swamps are nearly impassable 

 on account of the water present. 



Spruce forms from thirty to fifty per cent of the number of 

 trees, both red and black spruce occurring. Other conifers 

 which thrive here are balsam, northern white cedar, and tama- 

 rack. 



Among the hardwoods, black ash, soft maple, and yellow birch 

 are the most common. 



The character of the growth is poor; this is well shown in the 

 spruce which, on the average, is small when compared with 

 spruce timber on the other types. Two causes are assigned as 

 contributing to this small size. First, the growth is slow and 

 it takes the individual trees much longer to attain a given diam- 

 eter than on less swampy sites. Second, due to the great danger 

 from windfall on the soft, wet land of this type, the chances are 

 very much against individual trees attaining any considerable 



