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‘* ROUGH-BARK ”’ DISEASE OF YELLOW NEWTOWN APPLE. 15 
SUMMARY. 
The ‘‘rough-bark”’ disease of the Yellow Newtown apple in Virginia 
is caused by a new species of fungus, to which the writer has given 
the name Phomopsis malt. 
As trees which are in good growing condition are usually exempt 
from attacks of the fungus, fertilization and cultivation, together with 
proper pruning, should act as preventives, and as checks where the 
disease has already gained a start. Spraying is apparently effective 
only in so far as it contributes to the general health of the tree. 
The fungus will grow on leaves in spots previously diseased, often 
following Sphaeropsis malorum very closely in early spring, but is 
probably not a serious leaf disease. 
A rot of the apple may be produced by this organism, but is prob- 
ably of rare occurrence in nature. 
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