44 FOREST TREE DISEASES. 



is usually somewhat darker than normal. Split heart- 

 wood shows numerous perpendicular white spots or hol- 

 low pits, lacking, however, the black centers of those in 

 wood destroyed by root fomes. (PI. VI.) In species 

 which do not contain much resin the decay may attack 

 the sapwood also. 



The fungus gains entrance through knots and wounds, 

 and grows in the tree for some time before the fruiting 

 bodies develop. To destroy these does not destroy the 

 fungus itself, and new fruiting bodies are soon formed 

 in place of old ones. Trees infected with ring scale 

 fungus should not be tolerated in the forest. 



CHALKY QUININE FUNOUS. 



The chalky quinine fungus (Fomes laricis, Pis. VII 

 and VIII), forms, together with Trametes pini and 

 Armillaria meUea, the only serious menace to sugar 

 pine, on which it is most often found. It may, how- 

 ever, attack Jeffrey, yellow, and lodgepole pine, Doug- 

 las fir, and other conifers. The fungus causes a red 

 heartrot, with felts of white mycelium resembling 

 somewhat the decay produced by the sulphur fungus. 

 On sugar pine the fruiting bodies are generally very 

 large, round, and hoof-shaped, with a rough, white 

 chalky surface, which becomes slightly yellow or light 

 brownish with age. The substance of the perennial 

 fruiting body is white, soft and mushy when fresh, 

 chalky and friable when dry, and extremely bitter to 

 the taste. When rubbed, the surface stains the fingers 



