.-4- 
than nicotine sulfate 1:250. Dusts were, not so effective as in 1955, 
although they protected the vines from serious injury and were applied 
much more quickly, and easily than the sprays. Pyre thrum- clay dust 50: 
70 gave slightly better control than derris or cube dusts. 
The same station- ( 271 ) in 1953 reported that the liquid sprays 
were consistently; superior to the dusts, although the cube-clay dust 
containing 0.6 percent of rotenone was nearly as effective. As in 
other years, the spray consisting of nicotine sulfate 1:500 plus summer- 
oil emulsion 1:100 was the most effective treatment and reduced the 
borer injury 88.59 percent. The wettable cube spray using 4 pounds in 
100 gallons of water. showed a reduction of 81.55 percent and, being less 
expensive, would seem more practical. Contrary to the results in 1956, 
the pyrethrum-clay dust containing 50 percent of pyre thrum powder was 
ineffective. 
Treatment 
Check 
Nicotine sulfate 1:500 
+ oil emulsion 1:100 
Wettable cube spray, 4 
lbs. in 100 gallons 
Nicotine sulfate 1:250 
Cube-clay dust, 0.6 per- 
cent of rotenone 
Derris-clay dusf"^ 0.6 
percent of rotenone 
27 
1.48 
Average borer 
Reduction in injury 
Plants 
tunnels per 
over check 
vine 
Number 
Number 
Percent 
25 
5.68 
19 
.42 
88.59 . 
28 
.68 
81.55 
22 
.77 
79.08 
25 
-.84 
• 77.81 
59.79 
Pyrethrum-clay dust, 50 
percent of pyre thrum 
29 
2.06 
44.05 
The average field infestation in hubbard squash at Ysaltham in 1957 
wa: 
■2 <*■ 
.68 borers per vine, which is throe times as heavy as last year, 
W 
Derris powder, 1956; othor powders, 1957. 
