18 The New York State College of Forestry 
Spruce Flat: 
This type has been effectively described by Graves (1), and 
the chief purpose of discussing it here is to designate its limits 
so that it may be identified on cut and burned land. The type 
may be crowded out in some places by the abrupt approach of 
steep hardwood slopes to the edge of a swamp, and again the 
spruce flat may cover extensive areas around the swamps on 
the flats, knolls, and lower ridge slopes. The lower margin 
extends to the edge of the swamp, stream, or lake and is marked 
by the appearance of soft maple and birch on a moist soil covy- 
ered with humus and lacking the spongy characteristic of the 
swamp. | 
The upper margin is marked by the disappearance of balsam 
and appearance of beech in the mixture. The soil loses its 
humus covering, and there appears instead a shallow layer of 
hardwood leaf mould with a firm, well-drained soil beneath. 
Sugar maple is not commonly found in this type. The charac- 
teristic species are red spruce, balsam, hemlock, birch and red 
maple. Graves (1) gives 12.7 birch trees nineteen inches and 
over in diameter®* per acre which is 19.71 per cent of all species 
on an average of 106 acres. Birch exceeds in number all other 
hardwood species in the type. The predominance of softwood 
species, and moist condition of soil when shaded, and extreme 
dryness when not shaded, influence to a marked degree the 
reproduction in this type. 
Hardwood: 
This type has been defined as to its lower margin, and needs 
only general characterization. While that zone of the ridge 
slopes having comparatively deep soil may be defined as hard- 
wood type up to the point in elevation where spruce again 
appears as the dominant, there is still a wide variation in hard- 
wood areas. The amount of moisture and soil depth both influ- 
ence the composition. ‘The lower, moist hardwood land will 
have more birch than the better drained parts. Knolls with 
deep humus are usually covered to larger extent by softwoods. 
* Diameter is used to mean diameter at breast height outside bark. 
