LUTHER BURBANK 



and shriveled on one or two large limbs of the 

 tree when no other part of it is affected. But in 

 the ensuing season the disease is sure to spread, 

 and the tree seldom survives beyond the third year. 



As yet no way of combatting the pest has been 

 suggested, except the heroic measure of cutting 

 down trees immediately they are attacked, and 

 burning every portion of their bark. In this way 

 it is hoped to limit somewhat the spread of the 

 disease but it is by no means sure that the method 

 will be effective. There appears to be danger that 

 the pest will spread until it has decimated the 

 ranks of the chestnut throughout the eastern 

 United States; and of course there is no certainty 

 that it may not find its way to the Pacific Coast, 

 although the lack of chestnut trees in the desert 

 and plateau regions of the middle west may serve 

 as a barrier. 



The precise origin of the fungus that causes the 

 disease was not known until the summer of 1913, 

 when it was discovered by Mr. Frank N. Meyer, of 

 the United States Department of Agriculture, that 

 the fungus (which bears the name Endothia para- 

 sitica) is indigenous to China. The Oriental chest- 

 nut trees have become practically immune to it, 

 however, and it does not destroy them, but merely 

 blemishes their bark here and there with canker 

 spots. No one knows just how the disease found 



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