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The mildewy character is more easily observed in this latter case 
because it extends over larger areas on the leaf, stem or berries. 
While it is more commonly present, it is less destructive than the 
Downy Mildew. 
Symptom*. — On the vpper side of leaves the mycelium of this 
fungus forms a cobwebby patch of delicate white threads — often the 
larger part of the leaf is covered in this way. After the disease 
has grown for some time the appearance of the leaf is gray, and if 
the mycelium is rubbed off, the green of the leaf may be seen with 
brown spots where the tissue has begun to collapse under the 
blighting influence of the mildew. Foliage attacked by mildews soon 
become so weak that they cannot perform their natural functions 
and turn yellow and die; the plant bearing them weakens in con- 
sequence and the fruit fails to be developed. When these mildewy 
patches are well-developed, numerous small globules in various 
shades of yellow, brown and black are scattered over them. These 
are perithecia of fruiting bodies which contain the winter spores 
for the reproduction of the fungus. When in large number they 
give a powdery appearance to the surface and hence, the name of 
Powdery Mildew. Under the compound miscroscope these peri- 
thecia are seen to have hair-like appendages with spiral tips and 
for this reason the specific name of the fungus is spiral!*. \ jj 
Any of the green parts of the vine or the young berries may be 
attacked by this fungus. The berries remain small when mildewed 
and become brittle. They split open often, showing raw tissue. Such 
fruit of course never ripens, but the greatest injury is to the vine and 
crop of the succeeding year. A weakened vine cannot support a 
crop of fruit. 
Remedy. — As the mycelium of this fungus is external to the plant, 
it is not necessary to apply the remedy until the first evidences of its 
presence are discovered. As already stated, dry weather favors the 
development of this disease. Spraying the vines with Bordeaux 
mixture, as for Black Rot or Downy Mildew, will serve also to keep 
down the Powdery Mildew. If later spraying than August 1 is 
necessary it is better to use ammoniacal solution of carbonate of 
copper. This will leave no deposit on the fruit as the Bordeaux mix- 
ture does to the detriment of the fruit for marketing. 
RIPE ROT. 
( Gloeosporium fructiqenum.') 
This fungus at lacks several kinds of fruits at the time of ripening. 
It seriously impairs the flavor of the fruit by making it taste quite 
bitter, and for this reason this rot is sometimes called Bitter Rot. 
Symptoms. — The berries are attacked just as they are ripening 
