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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