234 THE GRAPE CULTUEIST. 



young wood and berries. Occasionally, however, it 

 appears earlier in the season, and in such cases is often 

 very destructive to the plants. It forms on the various 

 parts attacked, a powdery, mealy growth, this being 

 very marked on the leaves, where it is usually more 

 abundant upon the upper surface. The berries attacked 

 often crack, exposing the seed in a very peculiar manner. 

 Upon close examination of any part of the vine affected 

 with powdery mildew, fine delicate threads, which make 

 up the vegetative portions of the fungus, may be seen. 

 This, in itself, is enough to distinguish the disease from 

 downy mildew, the only malady for which it is likely to 

 be mistaken. 



Black Rot (Laestadia Bidwellii). This is such an 

 old, widespread, and well known disease, that it is 

 scarcely necessary to describe it. But there may be some 

 vineyardists who do not know that the fungus usually 

 appears first on the leaves and young shoots, in the form 

 of reddish brown, or black spots, and some two or three 

 weeks later it attacks the berries, and the first indica- 

 tions of its presence on these are one or more brown, or 

 blackish spots on the skin. The fruit soon turns brown, 

 then black, and finally becomes hard and ceases to grow, 

 and withers upon the stalks. Fig. 95. 



Anthracnose (SpJiaceloma am,pelinum), is caused 

 by this microscopic fungus, and, like the downy mildew 

 and black rot, it attacks the leaves, young tender shoots, 

 and the immature berries. The leaves, when first 

 attacked, show minute blackish-brown spots, which are 

 surrounded with slightly raised darker colored margins. 

 On the shoots the disease appears very much as it does 

 on the leaves, but as it progresses the spots become 

 darker at the center, and often run together, forming 

 elongated patches, which gradually eat their way into 

 the wood. 



Anthracnose on the fruit is usually called bird's-eye 

 rot, and first appears as a blackish or brown circular 



