FOREST INSECTS AND FUNGI 



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with easily wounded bark, the disease may start at any point. 

 When old trees are injured by fire, even to a very slight extent, 

 the disease will find entrance at the base. 

 There are several ways in which the work of this fungus can 



Fig. 45. A forest-grown chestnut on the edge of a recent cutting killed the previous 

 season by the chestnut bark disease. 



be recognized. The spots or cankers are apt to have an ellip- 

 tical form, and the bark over the injured part is somewhat 

 reddish and sometimes appears sunken. Pustules, of a yellow- 

 ish or orange color, containing the spores can often be seen pro- 



