60 Forest Club Annual 





reported to be dying on a large tract of timberland in Indiana 

 County, Pa. An examination showed the chestnut trees to be 

 in a very unhealthy condition. A greater part of the coppice growtn 

 in the woodlot was dead or dying. The woodlot had received no 

 care and was in a very poor silvicultural condition, greatly in 

 need of a thinning. The trees composing the over-story formed 

 a canopy so dense that the young coppice growth was dying out 

 from a lack of light. Almost as soon as the young trees died 

 a number of saprophytic fungi gained a foothold and developed 

 rapidly. The more common species of saprophytes found may be 

 included under the following genera : Nectria, Gloesporium, Cyto- 

 spora, Endothia and Valsa. The old veterans were also found 

 to be dying, probably as a result of the parasitism of the rhizo- 

 morphs of the root-rotting fungus, Annillaria niellea. A number 

 of branches bearing small cankerous areas were brought into the 

 laboratory and kept in damp chambers for ten days. No fungus 

 growth of any description appeared. As soon as the tissue of 

 the area was killed the saprophytes began to grow. They grew 

 to the edge of the area but not beyond into the living tissue. 



When an attempt was made to determine the extent of the 

 disease in western Pennsylvania, a perplexing condition arose 

 which was apparently the blight in a few of the extreme south- 

 western counties. In these localities this fungus was found to be 

 quite common on the chestnut trees. Superficially it could not 

 be distinguished from the true blight fungus but it was appar- 

 ently causing no serious injury to the trees. One of the most 

 characteristic features of the true blight is the presence of fan- 

 shaped areas of fungus mycelium on the bark on the scalloped 

 advancing edge of the canker. These areas are entirely absent 

 in the bark of trees infected by the "western Connellsville fungus" 

 as we will, for the sake of convenience and brevity, call this 

 fungus. Many theories were advanced to explain its peculiar 

 behavior in this locality. Some believed that it was due to the 

 large amount of coal smoke in the southwestern Pennsylvania 

 atmosphere. Others thought that the trees here were more re- 

 sistant to the disease. Still others considered it a saprophytic 

 strain of the true blight, Diaporthc parasitic a,, as described by 

 Murrill, while some advanced the theory that this was the sapro- 

 phytic progenitor of the deadly eastern parasite. The uncertainty 

 about the relation of these forms caused much confusion as to 

 the extent of the disease. 



In external macroscopical appearance this fungus resembles 

 the true blight fungus in all of its stages and there seems to be no 

 way in which it can be distinguished from the true blight fungus 



