62 
BULLETIN 55, U. S. DEPARTMENT OF AGRICULTURE. 
SILVICULTURAL SYSTEMS OF CUTTING. 
Upon the methods of cutting adopted in spruce stands will depend 
whether the future forest will be chiefly spruce or balsam or whether 
there will be future growth at all. In discussing these methods the 
economic limitations and specific conditions which may affect their 
application are not considered. These must necessarily differ for 
each particular forest tract. In a general discussion of the silvicul- 
tural system adapted to spruce and balsam it is possible to lay down 
only general principles. 
Natural reproduction may be secured in spruce-balsam fir stands 
by two methods: (1) Clear cutting and (2) gradual cuttings. 
In clear cutting, natural reproduction from stands adjoining the 
cutting must be relied upon to restock the area. The size and form 
of the clear-cut areas are therefore factors in the success of the repro- 
duction. If natural reproduction is desired, the greatest width of the 
Fig. 6. — Results secured by logging on the leeward side of balsam fir-spruce stands. The youngest stands 
are found on the windward side and deflect the wind upward, preventing windfall among the older 
area to be cut clear in spruce-balsam fir stands should not exceed 
double the height of the adjoining stand from which reseeding is 
expected. For example, if the average height of a spruce and 
balsam-fir stand is 75 feet, then the width of the area which is to be 
cut clear should not be greater than 150 feet. The length of the area 
does not affect the natural reproduction and should depend, there- 
fore, upon the amount of timber to be cut, convenience of logging, 
and similar considerations. In general, then, clear cutting with 
natural reproduction in spruce-balsam fir stands should take the 
form of long narrow strips. 
Since both spruce and balsam are shallow-rooted trees and there- 
fore subject to windfall, logging operations should as far as possible 
always begin on the leeward side of the mature timber, and proceed 
against the wind. If logging were to begin on the windward side 
there would always be danger from windfall in the stands adjoining 
the logged area. When the entire forest is cut over in this way, 
the youngest stands will be on the windward side, their tops forming 
a gradual ascending plane (fig. 6). The wind is thus deflected 
CLEAR CUTTING WITH NATURAL REPRODUCTION. 
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trees. 
