80 
THE GRAPE ROOT-WORM. 
In examining the yields for the various plats it will be observed 
that in the first year of the experiment plats I, II, III, and IV fell con- 
siderably below the unsprayed and unfertilized plat. This condition 
is due in a great measure to the fact that vines in plats V, VI, and VII 
were in a somewhat more thrifty condition at the outset of the experi- 
ment. The soil in these plats grades to a clay loam and has been 
enriched somewhat by the wash from an elevation immediately south 
of them. While the untreated plat shows great improvement in 
yield simply as a result of thorough cultivation, yet the annual 
increase in yield on this plat was much less than that upon the 
treated plats in the same soil. 
In addition to this increase in crop yield there was noted a great 
improvement in the quality of the fruit both in size of berries and of 
clusters. Plate IX, figure 2, gives a comparison of the size and com- 
pactness of fruit on a vine in the sprayed portion as compared with 
fruit on a vine in the unsprayed portion shown in Plate IX, figure 1. 
It was also found that the fruit in the sprayed plats remained firm 
and that there was practically no loss from shelling of the berries, 
whereas the fruit and stems in the unsprayed plat were badly mildewed 
and there was a great deal of shelling of berries. This benefit is 
derived from the fungicidal effect of the Bordeaux mixture. This 
increase in crop yield has also been accompanied by a marked improve- 
ment in the vigor of the vines throughout this vineyard. Practically 
all of the vines are now in a condition to produce a full crop of fruit, 
and there is no reason why this vineyard should not continue to 
produce as profitable crops as it did previous to its infestation, pro- 
vided it is subjected to treatment similar to that which it has received 
during this investigation. 
Plate VIII affords a comparison of the growth of vine at the 
beginning and at the end of the experiment, the upper figure show- 
ing the vineyard at the beginning of the experiment, and the lower 
figure after three years' treatment. 
RENOVATION EXPERIMENT ON A YOUNG VINEYARD. 
About the year 1900 there was a heavy planting of new vineyards 
throughout the Lake Erie grape belt. Scarcely had these young 
vines come into bearing when the owners noticed a rapid decline 
both in their crop yield and in vigor of vines. Close observation 
indicated that this decline was due largely to injury by the grape 
root-worm, and that the decline of these young vines was even more 
rapid than in the case of older, well-established vines. In many 
vineyards it was found that young vines had been killed outright in 
a single season. 
