CONTROL OF DECAY IN PULP AND PULP WOOD 
69 
Although at the outset care was taken to bring the pulp in the tests 
to a uniform condition of moisture the tables show that at the end the 
individual samples varied considerably, ranging from 53.6 to 73.3 
per cent in moisture content. The average was 65 per cent, as com- 
pared with the approximately 70 per cent which pulp normally has 
when taken from the wet machines. 
Table 15 gives the results obtained with 13 species of hymeno- 
mycetes — 12 isolated from ground wood, and one (6920-2) from 
sulphite pulp. It will be noted that the figures recorded in Table 
15 show results quite different from those in Table 14. Seven organ- 
isms caused sufficient color changes in the pulp to have appreciably 
discolored any paper manufactured from it. Five fungi made the 
infected pulp more or less brittle, and three caused it to become 
friable to the point of entire worthlessness. The most destructive 
of these organisms are those which are found most frequently on 
ground-wood. 
The moisture content of the pulp samples at the end of these tests 
was somewhat higher, averaging 68.7 per cent, than in the tests made 
with the molds, although efforts were made to start all exactly alike. 
The condition may be accounted for in some cases by the fungus 
trowing down into the water in the bottom of the jar, whence it con- 
ucted moisture to the pulp. All but two of the cultures remained 
viable until the end of 12 months. The two that died are not classed 
as vigorous wood destroyers. 
Table 14. — Deterioration of ground wood caused by 29 cultures of molds isolated 
from pulp and water 
Sample 
Culture No. 
Organism 
Per 
cent 
mois- 
ture 
Per cent loss in weight 
after— 
Physical condi- 
No. 
6 
months 
9 
months 
12 
months 
tion of pulp 
_196 
0.5 
1 
197 
G) 
""""676" 
>Normal. 
198 
[82219-11 
1 67.3 
f 69.0 
\ 61.1 
1 63.8 
f 66.6 
\ 65.1 
1 64.3 
{64.T 
1 57.6 
f 66.8 
\ 61.0 
1 62.0 
f 66.4 
\ 63.6 
I 72.6 
f 72.7 
{ 68.4 
1 58.1 
f 64.7 
\ 71.2 
I 73.3 
r~68.'9~ 
[ 59.0 
"67.T 
[ 60.5 
j"67.'8" 
I 63.4 
88 
1.0 
89 
1.0 
."§" 
]■ Do. 
90 
[62020-1 
1 
181 
.8 
182 
.8 
........ 
[ Do. 
183 
i32019-l 
Trichoderma sp. . 
65 
.3 
\ 
64 
.3 
""I.'o" 
[ Do. 
66 
[ 82219-10 
__do. 
85 
.5 
86 
1.0 
------ 
[ Do. 
87 
[6520-2 2 
do -- 
j 
190 
1.8 
192 
1.6 
""3." 2" 
\ Do. 
191 
[82219-6 
1 
112 
1.2 
j 
113 
1.1 
I.I" 
>Vei y slight pink. 
114 
[6520-1*. - — 
Aspergillus fumigatus.. _ 
Penicillium sp 
187 
188 
1.6 
j 
1.4 
""To" 
[Normal. 
189 
16 
17 
[81318-2 
.4 
j 
1.0 
."a" 
[ Do. 
18 
[l0918-9 
.. do 
j 
19 
20 
1.8 
1 
1.5 
"~"LT 
[ Do. 
[l0918-3 
37 
38 
.9 
1 
1.8 
~~"~2.Q 
[ Do. 
39 
1 
1 Contaminated with Penicillium sp 
s Isolated from water. 
