THE BED SPRUCE. 19 
and thus can be carried a long distance by the wind, variously esti- 
mated at from one-fourth to one-half mile. Its effective range under 
ordinary conditions is, however, very much less than that, probably 
not more than 200 feet. 
COMPETITIVE DISADVANTAGES. 
Spruce is subject to considerable competition with other species for 
the possession of the ground. In the mixed softwood and hardwood 
stands, beech and maple are its chief competitors; and in the soft- 
wood stands, balsam. Such species as witch hobble, briars, and the 
like often take possession of the ground after logging or fire, also fire 
cherry, aspen, and birch. These latter, however, soon open up their 
crown cover sufficiently to admit of spruce coming in beneath. 
The competition where briars and their associates occupy the ground 
after extensive cuttings or fire, is largely a matter of unfavorable seed- 
bed conditions. 
The competition of balsam, on account of its close association with 
spruce, is of vital importance. It almost invariably happens that on 
the replacement of stands where these two species occur in mixture, 
balsam largely predominates in the second growth. Balsam pos- 
sesses the two distinct advantages over spruce of a plentiful supply 
of seed annually and of a decidedly more rapid growth, particularly 
in the seedling stage. While the moisture, seed bed, and to a great 
extent the light requirements are about the same for both, the more 
rapid growth of balsam enables it to extend its root system more 
vigorously and thus become established more quickly and more 
firmly under seed-bed conditions in which spruce, although germi- 
nating with equal facility, is later exterminated through subsequent 
drying out of the upper layers before its roots have become firmly 
established. Soil acidity under spruce growth is supposed to be 
inimical to the development of the spruce seedling, while the balsam 
seedling is unaffected by it. Spruce, however, will come in under 
balsam without difficulty. This has led to the supposition that a 
balsam growth must intervene between successive growths of spruce 
in order to "sweeten" the soil. 
While the theory may be true, a contributory cause at least may 
be found in the character of the litter under the two stands. Spruce 
needle Utter, particularly under dense forest conditions, is very resist- 
ant to decay. It thus has a tendency to accumulate faster than it 
can be decomposed, forming an inert soil cover of considerable 
depth, resistant to root penetration and porous, quickly draining 
away the water close to the surface so much needed by the small, 
slow-growing root system of the young spruce seedlings. This handi- 
cap the more vigorously growing balsam seedling is able to overcome 
so as to establish itself in place of the spruce. But balsam needle 
litter, decaying much more readily than the spruce, does not accumu- 
