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DDT at 1 or 2 pounda per 100 gallons of water eliminated this species 
and also the rose leafhopper (Typhlooyba rosae (L*), both of which were 
rather abundant in an apple orohard in Hood River, Oreg*— Childs and 
Robinson (ill ) • 
Brythroneura oomes (Say), a grape leafhopper 
DDT-pyrophyllite (20-80) was used at the rate of 1 pound of DDT in 
100 gallons of water plus 1/2 pound of soybean flour* The spray was 
compared with a lead arsenate-bordeaux mixture* Applications were made 
at the rate of 200 gallons per acre on July 16 and 27* The entire Tine- 
yard wes treated with the DDT spray on August 9* Most of the spray was 
directed toward the upper surface of the leaves to avoid spraying Hxm 
fruit* 3h the plot receiving three DDT sprays the infestation disappeared 
after the seoond application* In the plot receiving one spray of DDT 
following two lead arsenate-bordeaux sprays, the leafhopper infestation 
was under control for about 10 days* There was no injury from DDT sprays 
to foliage.— K. J* Agr* Expt* Sta. (275) * 
The grape leafhopper was controlled by 3 sprayings with 1 pound of 
DDT per 100 gallons of water* — Hutson (220 ) . 
Brythroneura elegantula Osb*, a grape leafhopper 
DDT was tested against this important pest of grapes in the San 
Joaquin Valley, Calif* In these trials, DDT applied either as a vapo-spray 
or as a dry dust mixed with sulfur appeared to be effective against adults 
and nymphs of the grape leafhopper* Toxicity to nymphs persisted at least 
22 days* The effect of treatment was noticed 4 months after application* 
The vapo-sprays contained 0*6 or 1*2 peroent of DDT in a mixture of 10 
percent light summer oil (60 viscosity) and 90 peroent of kerosene* The 
dusts contained 50 percent of sulfur, sufficient A-K 20 to make 1, 5, or 
5 percent DDT, and the remainder Frianite.— Fraaier and Stafford (169 ) • 
Brythroneura variabilis Beamer 
A 5 percent DDT-oil fog made by feeding a DCT-oil solution into a 
current of steam proved effeotive in the Salt River Valley, Aril* First 
trial was on a 10-acre block of Bumstead grapes where leafhoppers averaged 
70 to the vine* A pick-up truok, carrying a generator, ran along two 
sides of the block for 7 minutes* In that time 14 gallons of orohard 
spray oil containing 5 percent of DDT was turned into a fog that was 
carried over into the vines by a light breeze . The population ]£ days 
later was 1 leafhopper per vine* In the next few days 100 acres were 
"fogged," with the same result. The leafhoppers were wiped out*— Anon* (49) , 
Vorhies and Wehrle (364) • 
