CHAPTER I. 



California Vine or Anaheim Disease Its Cause and Nature. 



This disease has been under my special observation for the last 

 five years. It may have been in this vicinity longer than that, but 

 if it was, I did not notice it. The varieties mostly affected are the 

 Muscat of Alexandria, Black Ferrara and Cornichon, and these only 

 in such places where the soil is rich the vines grew vigorously and 

 bore heavy crops. Where, for certain reasons, they did not grow 

 vigorous foliage or bear abundantly, whether the soil was poor or 

 rich, they have remained healthy so far. This seemingly would 

 prove the contention of some, that the heavy bearing of a vine is 

 the cause of the trouble. But Viniferas produce heavily also in 

 countries where the disease is unknown, besides vines have died 

 with it that did not bear at all. 



After observing the disease closely for the last four or five 

 years, I believe, I do not make a mistake when I claim, that its 

 prime cause is the great change in the moisture contents of our 

 soils from wet in the spring to dry during the latter part of the 

 summer; as it occurs in California on irrigated lands as well as un- 

 irrigated. If the soil was always as wet as in the spring or always 

 as dry as during the latter part of the summer, no matter how small 

 the growth of the vines, there would not be this disease. 



In order to prove this more clearly, I irrigated some Muscat 

 and Black Ferrara vines heavily during the fore part of June two 

 years ago, as well as last year, by soaking up the ground thoroughly 

 around them. The vines were about 15 years old and stood on 

 ground which had never been cultivated except the first ye^r or two 

 during their existence. The soil they grew on is a rich, deep, clayey 

 loam. As I left the trench unworked the water soon evaporated 

 and the ground was as dry as ever. Some of the vines had an attack 

 the first summer and the others this summer, while all the rest of 

 the vines on the same uncultivated ground, which were not irrigated, 

 are as healthy and thrifty as ever, in fact went through this last most 

 trying of all dry seasons in this locality better than any of my vines 

 on cultivated ground. This was because- the ground was dry al- 

 ready when they started growth in the spring and the change from 

 wet to dry, therefore not so great. I have made other observations 

 and conducted other experiments to prove this cause as asserted, 

 but it would lead off too far to explain them here. 



I suppose the roots of most vines are similar to cuttings ; if cut- 

 tings have been kept too wet and then are exposed to the air, they 

 will dry out in a short time and be worthless ; but if they have been 

 kept in dry sand, they will endure exposure for a long time. Stand- 

 ing in a wet soil during the forepart of the vines' seasonal growth 

 leaves the roots with less power to resist dryness later on. 



I guarantee that vines cultivated and irrigated both, as laid 

 down by myself in the chapter on preventive methods, will never 

 be attacked. On the other hand I guarantee to produce the disease 

 in a vineyard of a uniform clayey or loamy soil, where Viniferas on 



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