CONTROL OF PEACH DISEASES IX GEORGIA 19 
Life-history studies showed that in the season of 1923 there was 
only one generation of the curculio at Fort Valley, Ga. Similar 
studies had shown two complete generations in the season of 1921 
and again in that of 1922. Since there was only one generation in 
1923, the early applications of arsenate of lead did not have a chance 
to prove their effectiveness against a second brood of larvae. There- 
fore, as shown in Table 8, there was little difference between the 
number of the curculio-infested peaches from the plats that received 
the early spray and those that were not sprayed until the calyces, 
or "shucks, " were shedding. Since there is no way to predict accu- 
rately early in the season whether two generations of the curculio 
will occur, or only one, peach growers could not afford to omit the 
early arsenate-of-lead treatment, as this materially reduces the 
size of the second brood of "worms" in years when two generations 
occur. 
In 1923 the curculio infestation in the experimental orchard of 
Hiley peaches was light, as only 6.4 per cent of the fruit harvested 
from the check, or untreated, plat was "wormy." The spray 
schedule recommended to the growers, which was the one used 
in treating Plat I, gave the best control of the curculio. 
The control of the curculio, as shown by the percentage of infesta- 
tion in the harvested fruits, was not quite so good in Plat III, which 
received four applications of arsenate of lead in the proportion of 
three-fourths of a pound to 50 gallons of spray, as in Plat I, which 
received three applications in the proportion of 1 pound of arsenate 
of lead to 50 gallons of spray. (Tables 8 and 9.) Moreover, the four 
applications of the less poisonous spray were otherwise less desirable 
than three applications of the stronger, because of the greater injury 
which the former inflicted on the foliage. 
Three applications of self-boiled lime-sulphur gave slightly better 
control of brown rot (Table 8, Plat III) than two applications. The 
control of scab was also somewhat better from the three applications. 
Since in previous years it had been found unnecessary to make an ap- 
plication for the control of scab earlier than about four weeks after the 
falling of the petals, it is probable that if in the plats receiving two 
applications of the fungicide the first application had been made 
slightly earlier, control would have been as good as in the plat receiving 
three applications. The addition of calcium caseinate did not in- 
crease the effectiveness of the arsenate of lead used for controlling the 
curculio in either the "drops" or the harvested fruit. The plat 
receiving the regular treatments but with the addition of calcium 
caseinate to all sprays yielded harvested fruit with a smaller per- 
centage of brown rot (Table 8, Plat II), but the scab on this plat 
was heavier. The differences, however, were too small to be signi- 
ficant. 
The two different mixtures of sulphur, hydrated lime, and calcium 
caseinate used on Plats V and IX gave very satisfactory control of 
brown rot and scab, but there was more burning of the foliage in 
these two plats than in any other plat in the orchard. While this 
burning was not nearly so severe as that obtained from the mixture 
used in 1922, it was too serious to warrant an unqualified recom- 
mendation of the mixture for use in the South. It should be noted, 
however, that arsenate of lead was used with it in both applications. 
The spray continued to give better control of curculio and brown rot 
