14 BULLETIN 55, U. S. DEPARTMENT OF AGRICULTURE. 
Though the inferior quality of wood pulp containing a large amount 
of balsam fir can not be denied, it is probably not altogether due to 
the inferiority of the balsam wood, but to deficient knowledge of how 
to properly manufacture it into paper. 
WORKING UP BALSAM FIBER. 
There is no doubt that the fiber of balsam fir is weaker, shorter, 
and softer than spruce fiber; therefore the prevailing practice of 
working up balsam fir with spruce in both mechanical and chemical 
processes ordinarily results in an inferior grade of pulp, if the admix- 
ture of balsam is considerable. This is not so perceptible in the 
sulphite process as hi the ground pulp. The wood of balsam fir, 
being softer, cuts more easily than spruce wood; therefore a stone of a 
sharpness and at a given pressure to produce good strong pulp from 
spruce makes poor pulp from balsam fir. With dull stones and 
light pressure a better quality of pulp could probably be made from 
balsam. Similarly, in the case of chemical pulp better results could 
most likely be obtained if weaker acids more suitable to the softer 
nature of balsam-fir fibers were used. The different properties of 
wood of spruce and that of balsam fir naturally suggest a different 
treatment of their fibers, which could best be accomplished by han- 
dling them separately. Experiments in this direction would probably 
open a much larger field for the use of balsam pulpwood than it now 
has. 
SMALL YIELD OF WOOD FIBER. 
Another drawback to balsam as compared with spruce is its smaller 
yield in pulp and paper per cord of wood. Being lighter than spruce 
when seasoned, it contains less wood substance per cord and so yields 
a smaller amount of pulp. The following figures regarding the yield 
of chemical and mechanical pulp per cord of spruce and balsam are 
based on actual experience and may be considered as average: 
Ground 
pulp. 
Chemical 
pulp 
(sulphite). 
Pounds 
per cord. 
1,800 
1,500 
Pounds 
per cord. 
1,200 
1,000 
Balsam fir 
This drawback, however, would not exist if the stump age price of 
balsam pulpwood were proportionately lower than instead of being 
nearly the same as that of spruce. Some mill men even claim that the 
only objection they have against balsam fir is its smaller yield hi pulp, 
which, at the same stumpage price as spruce, makes its use unprofit- 
able and discourages any attempts to improve methods of utilizing 
or manufacturing it. 
