In this study both brown and white rot, in both the incipient 

 and typical stages, were considered to be cullj therefore, the cull 

 factors discount all decayed wood. In certain uses for timber it may 

 be desirable to know the type of rot or stage of decay likely to be 

 found in the cull of a tree species. Table 2 shows for the various 

 tree species the percentage of each type of rot in each stage of 

 decay based on the cubic-foot volumes of cull found in the study 

 trees. 



If timber is to be used primarily for pulp, it will undoubt- 

 edly be desirable to know what percent of the total cull is caused by 

 white rot and what part of the white rot is in the incipient stage of 

 decay. Since all ci±)ic-foot cull was caused by decay, the signifi- 

 cance of each type of rot and each stage of decay in the total cull 

 of a tree species can be read from table 3. 



Table 2. — Percent of xrrhite rot and brown rot in each stage of decay 



by tree species. 



Tree species 



: Uhite rot 



: Brown rot 



: All rot 





: Incip, : Typ. 



: Incip. : Typ. 



: Incip. : Typ. 



Sitka spruce 2? 73 39 6l 37 63 

 Western hemlock 36 6k 36 6k 36 614. 



Western redcedar 77 23 57 k3 77 23 



Table 3. — Percent of total cubic cull volume caused by each type of 

 rot and stage of decay in each tree species. 



Tree species : White rot t Brown rot 





: Incip, 



: Typ. 



: Total 



Incip, 



: Typ. 



: Total 



Sitka spruce 



k 



12 



16 



33 



51 



81; 



Western hemlock 



22 



ko 



62 



lli 



2li 



38 



Western redcedar 



76 



22 



98 



1 



1 



2 



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