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Walker (451) in 1937 recorded tests with a sodium salt of water- 
soluble petroleum oil sulfonates designated as Ultrawet which possesses 
desirable qualities as a wetting and spreading agent for spray materials. 
Ultrawet at 1:1600 in water did not damage the foliage of many economic 
plants. Ultrawet is compatible with the insecticides and fungicides in 
common use. 
The addition of Ultrawet to cube dust resulted in increased control 
of the potato flea beetle. The addition of Ultrawet to cube in sprays 
gave promising results in controlling onion thrips. The use of Ultrawet 
with cube root in sprays to control the European corn borer gave slightly 
increased protection. 
Ultrawet added to sprays and dusts to control the Mexican bean 
beetle, striped cucumber beetle, imported cabbage worm, nnd cabbage looper 
did not provide increased protection. 
One-half pound of Ultrawet added to 3 pounds of cube (4$ rotenone 
and 14$ total extractives) in 100 gallons water increased the control of the 
pea aphid from 93.5 to 98.7 percent and 1 pound of Ultrawet plus 3 pounds 
of cube gave a control of 98.8 percent. Ultrawet was added to derris-clay 
dust (0.75% rotenone) and also cube spray (3 lbs. per 100 gels.) and in 
both cases its addition enhanced the control of the potato flea beetle. 
Bordeaux (4-4-50) plus 4 pounds of cube per 100 gallons was increased 
in effectiveness in the control of European corn borer in potatoes by the 
addition of Ultrawet 1:1600. 
In tests against onion thrips, 4 pounds of cube per 100 gallons plus 
pounds of a mixture of sulfur and Ultrawet (16 to l) gave a control of 
56.4 percent as compared with 31.4 percent for the same mixture without 
cube. 
Tests with miscellaneous truck croj^ pests. — Cube dusts (0.75 per- 
cent rotenone) and sprays (3 pounds per 100 gallons) were used to control 
the Mexican bean beetle*, Spilachna varivestris Muls. , the striped cucumber 
beetle. Diabrotic a vittata Fab. , the imported cabbage worm, F ieris rapae L. 
and the cabbage looper, Auto graph a brassicae Riley, both with and without 
Ultrawet. Im most cases the addition of Ultrawet did not result in in- 
creased protection of the plants from these pests. The sprays and dusts 
without Ultrawet usually provided control. 
Bromley (51) in 1937 reported that sprays of rotenone and other 
toxic extracts from derris and ciibe, if used at sufficient strength and 
with satisfactory wetting agents, will kill certain unprotected insects, 
but their use in shade tree spraying is to date rather limited. These 
materials possess little, value as stomach poisons. The derris or cube 
rosin-residue emulsion is a promising repellent for the Japanese beetle. 
Various insecticides, including derris and cube, are known to have 
repellent qualities against certain insects, but their use for this 
purpose has not been developed to any extent for shade trees as yet. 
