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 litter, 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- 



