DRY-ROT OF INCENSE CEDAR. 
31 
the work of the dry-rot fungus. The reader should remember that 
the percentage of cull based on the merchantable volume of the trees 
would be higher than the percentages here given, since these are based 
on the total volume of the trees outside bark and including the entire 
top. In the younger age classes up to 160 years the percentage of cull 
is small and variable, in one class higher in the suppressed, in another 
higher in the dominant, and in a third equal. But in the age class of 
161 to 200 years a decided jump in the percentage of cull occurs, 
particularly in the suppressed trees. "While the increase in the case of 
the dominants is only 3 per cent, in the suppressed trees it amounts to 
8 per cent, bringing the cull percentage to 12. In the next age class 
a still further change is apparent. Here the cull percentage in the 
dominant trees increases strongly, as does also the percentage in the 
suppressed trees, the latter still remaining considerably higher than 
the former. But in those subsequent classes which have a sufficient 
numbers of trees to make the data of value, the cull is higher in the 
dominant than in the suppressed trees. When the age classes are 
combined, the total cull is 4 per cent more in the suppressed than in 
the dominant trees. 
The salient features shown by Table II are the low percentage of 
cull in the younger age classes, the sudden increase earlier in the 
suppressed than in the dominant trees, which after it once begins goes 
steadily on with advancing age, and the higher percentage of cull in 
the suppressed trees as compared with the dominant trees in the two 
age classes which show the first sudden increase in this percentage. 
However, the percentage of cull caused by dry-rot is not the only 
figure of interest, since it is prerequisite that the trees first be infected 
and that these infections develop sufficiently to cause measurable 
cull. Table III gives the figures on percentage of infection and cull 
cases. The number of trees used as the basis and the average age 
are the same as in Table II. 
Table III. — Infections and cull cases found in incense cedars of the combined areas. 
Age class. 
Infections (percentage 
of total number of 
trees). 
Infections causing meas- 
urable decay (percent- 
age of total cull cases). 
Dominant. 
Suppressed. 
1 
Dominant. Suppressed. 

5 
33 
42 
62 
74 
82 
90 
87 
100 
100 

41 to 80 years 
12 
50 
62 
57 
71 
87 
100 
100 
100 

28 
35 
36 
56 
80 
86 
100 
100 
81 to 120 years 
15 
121 to 160 years 
28 
161 to 200 years 
44 
201 to 240 years 
63 
241 to 280 years 
78 
281 to 320 years 
88 
321 to 360 years 
361 to 400 years 
87 
100 
401 to 440 years. . 
100 
Combined 
61 
54 
41 | 42 
