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Nat Mey oh dea be a iS ED Pid Bi) Web be a EAR EL eee ohh ARN 
RRA DU eM a ONT TT CRRA IRC ONT IeT PONE OR 
320 REPORT OF THE Acute Panton iiee OF THE 
Speoisl attention has been directed to this subject during the 
past summer, and as the result of extended field observations i | 
have been forced to conclude that the grape-leaf spot fungus and — 
the fungus of black rot of grapes is one and the same. 
The brown spots upon the leaves figured and described in my _ 
report on the fungus diseases of the vine must, then, be regarded 
as simply the manifestation of the black rot on the foliage. 
The fact of the identity of the leaf form with that occurring 
upon the berries is especially important in connection with the 
“ question of treatment, for black rot, like the downy mildew, must 
be treated preventively. As a rule, the black rot fungus first 
attacks the leaves some days, and often a week or two before the 
berries are affected. It may be sometimes observed on the foliage 
even before the vines have bloomed. 
By watching the foliage, the vineyardist may be warned of the 
presence of this dreaded parasite in good season, and upon the 
first signs of its manifestations upon the leaves, he ought to begin — 
the application of remedies or preventives, in order to protect the 
fruit. Evidence: is accumulating that the sulphate of copper 
compounds possess some value in checking this disease. We 
have been assured, by some experimenters, that there was a very 
decided improvement in respect to black rot in vineyards treated 
with these preparations, compared with those not treated. 
Downy MILDEW. 
Peronospora Viticola (De By.) 
Appears in more or less conspicuous white patches. Pale 
green or yellowish spots of irregular size and outline, appear __ 
upon the upper sides of the leaves as the first manifestation of f 
the disease, corresponding points on the lower surface soon 
exhibit the outside development, the spore bearing filaments of 
the fungus, in the form of white patches that are very conspicuous 
on the smooth leaved varieties of grapes. As the disease pro- 
gresses, the yellowish spots of the upper surface assume a 
brownish hue, which gradually becomes more intense, finally 
having all the characters of completely dead and dried tissues. 
These spots may be quite small late in the season; the older 
leaves attacked are often covered all over with minute brown 
spots, which are usually sharply defined, being limited by the _ 
nerves in the leaf; again they may be so large as to nearly cover a 
