64 BULLETIX 1241, L\ S. DEPARTMENT Of AGKICULTURE. 
same kind of wood pulped when green. Even where wood was stored for a period 
of only one year pulp yields were one-seventh less than from the same kind of 
wood pulped when green. Likewise many cases were recorded where the actual 
cellulose content of pulp was reduced 5 to 10 per cent by storage under conditions 
favorable for decay. From these studies it was estimated that the total annual 
loss on mechanical pulp from decay while in storage is equivalent to approximately 
200,000 cords and that the loss of pulp wood in storage is 400.000 cords. The 
paper made from infected pulp was unsatisfactory in appearance and had half or 
less than half the bursting and tensile strength shown by paper from sound pulp. 
Storage losses from decay in both cases are due to improper methods and are, 
therefore, preventable in large part. Pulp-wood loss may be largely eliminated 
by keeping wood yards free from infected wood and bark, and by using the 
wood in rotation so that none is allowed to remain in the yard over a year. 
Losses of stored pulp from decay may be prevented by the use of preservatives. 
A further and very large loss occurs in the manufacture of chemical pulp, 
where on the average only approximately 45 per cent of the original weight of 
the wood is secured in pulp. The remainder is lost in the cooking liquors. Much 
time and money have been spent in research designed to eliminate these losses. 
Some hopeful results have been secured. For example, by proper cooking 
operations and methods of control, as demonstrated by both laboratory and mill 
tests, it is possible to increase the output of sulphite pulp from the same amount 
of wood by 10 per cent. This can be accomplished through minor modifications 
of the sulphite process now in general use. Any possible increase in pulp yield 
will obviously reduce correspondingly the amount of wood required for a specified 
volume of pulp or paper. 
MODIFIED PULPING PROCESSES AND WIDER LSE OF SPECIES. 
The number of species which have been regarded as suitable for pulp making 
has gradually increased, under pressure of high prices because of timber shonuee. 
and as a result of scientific investigations into the pulp-making properties of 
different woods and into the pulping processes. A new or modified pulping proc- 
hich would enable pulp from such woods as beech, birch, maple, and aspen 
to compete with mechanical pulp would revolutionize the situation in northern 
New England and would greatly relieve the crisis eve?: in New York. It would 
go a long way at lea.-t toward saving the present newsprint industry in these and 
other States, by affording time to get greatly increased timber growth under 
way. A process which increased the number of suitable species for sulphite 
echanical pulp, in particular, would be of great value in the solution of our 
entire future pulp-supply problem. 
A series of investigations covering the pulp prcx t the suitability of 
American woods foi pulp 1ms been under way in the Forest Service for a good 
many years. Preliminary results in one of these investigations justify comment. 
The wood in this experimenl A chipped in the normal manner for chemical 
. the chips are slightly but uniformly softened by chemical treatment and 
arc A hanically disintegrated. The high yields *-f 75 or 80 per cent of 
the original weight of the wood, the low cosl of the chemical treatment, and the 
r requirements indicate the possibility, in seme of the results very 
A obtained with hard . itisfactory pulp can 
be made I cost comparable with mechanical pulp. 
Spruce typifi< rigid requirements of the mechanical process, but the 
successful completion of this investigation would permit the substitution in 
mechanical pulp and heme in newsprint of woods of lower qualities which are 
fori is] irpose. The newsprint mills which experience 
difficulty in securing spruce ami tir pulp wood might be able to turn to the local 
