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 mferiority 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 prevailmg practice of 

 workuig up balsam fir with spruce in both mechanical and chemical 

 processes ordinarily results in an mferior grade of pulp, if the admix- 

 ture of balsam is considerable. This is not so perceptible in the 

 sulphite process as in 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 hkely 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: 



Spnice 



Balsam flr. 



Ground 

 pulp. 



Pounds 

 per cord. 

 1,800 

 1,500 



Chemical 



pulp 

 (sulphite). 



Pounds 

 per cord. 

 1,200 

 1,000 



This drawback, however, would not exist if the stumpage 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 in 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. 



