AT 



burn remained constant. That the injured trees were 

 most often attacked is evidenced by the fact that 75?» 

 of the pines attacked on the burn, had been slightly 

 or moderately injured by fire, B^o of the attacks were 

 on uninjured trees, and no trees killed by the fire 

 were touched. 



(6) -t^ama^e from Wood-destroy igg Fungi Following 

 Fire Injury 



Fungi, in the majority of cases, gain entrance 

 through open fire-scars, and the damage resulting there- 

 from may often be much greater than that from the fire 

 itself, ffire causes the largest and deepest wounds, 

 frequently burning deeply into the heartwood. Such 

 wounds expose the unprotected wood surface for long 

 periods of time before the tree can secrete sufficient 

 quantities of resins to resist the attacks of fungi. 

 Hence, practically all fire-scarred timber is injured 

 more or less by wood -destroying fungi. Fungi damage 

 seems to most extensive in white fir and incense cedar. 



Dr. J. S. Boyce of the Office of Investigation in 

 Forest Pathology, having made a study on the Pliimas Nat- 

 ional Forest and the Stanislaus Nat ional Forest , in Cal- 

 ifornia, found that of 1,075 typical trees felled and 

 dissected to determine the ml^thod of infieotion with dry- 

 rot fungus, 646 bore fire-scars, 6?^ of which had be- 

 come infected. As the entrance afforded by fire-scars 



