- 7 - 
The fungicides were applied about once a week, beginning about 10 days 
after seeding and ending 2 to 3 weeks before completion of harvest. 
The insecticide applications on cucumbers were made as shown in 
table 2. 
Control During Early Stages of Plant Growth 
Special efforts were made to find methods of evaluating the effec- 
tiveness of insecticides in pickleworm control before yield records 
could be obtained. Early-season control data were needed for com- 
parison of the more toxic materials, which should be used only during 
the prefruiting period of plant growth because of residue hazards. In 
the early experiments examination of squash plants from which yield 
data were to be secured did not prove feasible, because the plants had 
to be destroyed to find the larvae that had tunneled into them. The 
problem was even more complicated with cucumbers, because it was 
difficult to separate the plants after the vines became entangled. 
Examination of surplus plants at the time of thinning and of the staminate 
flowers later were possibilities explored in the fall seasons of 1948 and 
1949. 
The numbers of surviving insects on surplus plants at thinning time 
provided an indication of the effect of the insecticides on pickleworms, 
melonworms, and melon aphids. The information was limited, how- 
ever, by the small number of plants examined, the small size of the 
plants, the light infestation usually present at that time, and the few 
applications ordinarily made before thinning time. In spite of these 
factors, survival counts of the melonworm and melon aphid at this time 
seemed worth while. 
The number of pickleworms and melonworms (the former com- 
prising about 90 percent of the total) in the staminate flowers shortly 
before harvest was a reliable index to the effectiveness of the insecti- 
cides, being more closely correlated with yield data than counts made 
at thinning time. The pickleworm control in the flowers was usually 
higher than that obtained on the fruits. Control data based on flower 
examinations are limited, because ordinarily only small pickleworms 
feed in cucumber blossoms and many do not feed there at all. Squash 
flowers, however, are larger and larvae are able to complete develop- 
ment in them. Flower examinations made as near harvesttime as pos- 
sible should prove valuable, particularly in work with squash, if yield 
data cannot be obtained. 
