GRAPE DISEASES 267 



CALIFORNIA VINE-DISEASE 



Cause unknown 



Although this disease occurs in Italy, chief damage has been 

 wrought in California. At one time it was the most serious 

 of the several vine-diseases in that state. It first appeared 

 there in 1884, as nearly as can be determined, and within two 

 years many vineyards were destroyed in the vicinity of Ana- 

 heim, California. The destructiveness of the disease in this 

 locality has given rise to the name Anaheim disease. Up to the 

 year 1895 about 30,000 acres of productive vineyards were 

 killed. The loss has been estimated at not less than $ 20,000,000. 



Symptoms. 



Except for the older pathologists who have known the disease 

 from the first, few are able to recognize with accuracy the Cali- 

 fornia vine-disease. When it first appears in a vineyard it 

 shows here and there in a sporadic fashion. But in time it 

 increases; it is cumulative. The leaves, canes and roots are 

 affected. During the first season symptoms of the disease in 

 a vineyard show on the foliage. Small yellow spots appear in 

 the tissue between the veins. These enlarge and unite, form- 

 ing yellowish stripes which broaden and die at the center. 

 Eventually there is a conspicuous brown stripe of dead tissue 

 bordered by yellow on each side, leaving only a narrow band of 

 green tissue along the veins. Leaves fall prematurely, drop- 

 ping from the base of the canes first. The immature portions 

 of the canes turn black and die, and the berries become dry and 

 hang to the vine, or rarely fall. The next season there is a 

 reduced growth of the canes. Often the foliage will appear 

 normal in the spring, but it becomes spotted during the sum- 

 mer, followed by a premature defoliation and death of the 

 canes as described for the first season. The third spring the 

 vine may fail to put out new growth, or it may grow until 

 midsummer and then die. In some cases affected vines live for 



