22 UNIVERSITY OF CALIFORNIA EXPERIMENT STATION. 



sprayed with the acid iron sulfate on the 28th of March, just as the 

 buds were beginning to swell. Sections 3, 5, 9, and 11 were sprayed 

 with Bordeaux mixture (4 pounds of copper sulfate, 4 pounds of lime, 

 40 gallons of water) 011 the 6th and 26th of May, and the 16th of June. 



The growth of the vines on the sprayed and unsprayed rows was 

 sporadic and uneven. After the second spraying with Bordeaux mixture 

 the foliage of the sprayed vines was somewhat greener than that of the 

 witnesses. By the 16th of June, the date of the third spraying with the 

 Bordeaux mixture, no specific signs of disease had shown in either the 

 witnesses or the treated vines, other than such as might be referred to 

 known causes. The appearance of the plot was in no way such as to 

 create a fear that the vines would collapse and fail to ripen their fruit. 

 On the 27th of June the general appearance of the vines was somewhat 

 wan, and the line of demarkation between the sprayed and unsprayed 

 vines had well-nigh ceased to exist. On the 12th of July, however, 

 almost every vine in the plot showed unmistakable signs of suffering; 

 the foliage was pale, and many clusters of grapes had already shriveled, 

 or were just beginning to collapse; there was no longer any difference 

 between the witnesses and the sprayed vines. In fact, so general were 

 the symptoms of disease in both the treated and untreated vines that 

 any further attempt to check it with Bordeaux mixture was given up as 

 useless. By the end of July practically every vine in the experiment 

 plot was affected with the Grape-shrivel, with the exception of the Zin- 

 fandels and the non-grafted Lenoirs. 



On the 21st of July, when well-nigh every vine in the plot was affected 

 with the Grape-shrivel, the free moisture in the soil, a loam underlaid 

 at the depth of two feet with a gravelly clay-subsoil, varied between 

 nine and ten per cent. 



The roots of the stock in different parts of the plot were examined 

 from time to time for the purpose of determining their resistance to the 

 Phylloxera. Nodosities were always found to be present in plenty, both 

 on the grafted and on the non-grafted Lenoirs. 



At the end of July one per cent of the vines in the experiment plot 

 were dug up, split open and examined. The result of this examination 

 is given on page 20, where the internal appearance of the shoots, spurs, 

 and body of vines affected with the Grape-shrivel is described. 



In the beginning of August a critical examination was made of the 

 vines in the plot, for the purpose of determining if there was any rela- 

 tion between the vigor of the vine or of any of its individual shoots, 

 and the Grape-shrivel. The only fact this examination clearly revealed 

 was that the vines had been given too liberal a pruning. In general, 

 no more than half the eyes left at pruning time had sprouted, and 

 sometimes less. 



The yield of the experiment plot (one acre) was about 700 pounds of 



