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TWENTY-NINTH FRUIT-GROWERS' CONVENTION. 



ance it had ruined at least twenty-five thousand acres of vines in what 

 are now the counties of Orange, Los Angeles, San Bernardino, Riverside, 

 and San Diego. This involved a direct and indirect loss of not less 

 than $30,000,000. 



About five years later, in 1889-90, the same disease broke out in the 

 upper end of the Sacramento Valley, and old Mission vineyards both east 

 and west of the Sacramento River, in Tehama County, died in a single 

 season. Since that date extensive vineyards have been killed in Tehama, 

 Butte, Colusa, Yuba, and Sutter counties, and many others have been 

 practically ruined. Probably five thousand acres of vines have been 

 destroyed in that section of the State since the date named. 



A third extensive viticultural center has more recently become 

 affected by the same disease. About 1898-99 the great vineyards of the 

 Santa Clara Valley began to fail in a manner similar to those of south- 

 ern California and those of Tehama County. The death of vines in the 

 Santa Clara Valley has been rapid over large areas, while toward the 

 east side of the valley and among the Santa Cruz Mountains at the 

 west the destruction has been slower and is still progressing. The 

 affected district includes portions of the counties of San Mateo, Santa 

 Clara, Santa Cruz, and Alameda. It is probable that the loss will 

 amount to ten thousand acres of vines in this district, as nearly or quite 

 that acreage is already affected. 



We have then, in general summary, a destruction of forty thousand 

 acres of vines by this disease in the course of the past twenty years — 

 1884 to 1904 — and a direct and indirect financial loss to the State and 

 country from this cause of probably not less than $40,000,000. 



In both southern California and the upper end of the Sacramento 

 Valley the California vine disease has destroyed the vineyards wholly 

 independent of the action of phylloxera, which pest, so far as known at 

 present, does not exist in either district. In the Santa Clara Valley, 

 however, phylloxera has been present for some years, so that both 

 diseases must be taken into account in considering the effects in that 

 locality. 



A broad study of the appearance and development of the California 

 vine disease in the three great viticultural districts now affected, reveals 

 certain prominent facts that should be noted by those interested in 

 vine growing: 



(1) The disease is more apt to develop in a region where the vines 

 have been weakened by some cause — such as the injur}^ of the root 

 system by drought or excessive moisture, or by sudden changes from 

 one to the other. 



(2) The disease when once established in an epidemic form remains 

 in the affected region in an active state, destroying new vineyards set 



