-55- 
A knapsack sprayer was used in making five applications of 20 per- 
cent DDT spray on early potatoes and three applications on late potatoes. 
Potato leafhopper oounts with the different treatments varied consider- 
ably, but the population was definitely lower on the DDT plots than on 
the check.— Gould (184) » 
La the laboratory Gesarol A-3 dust killed 96 percent of the adult 
leafhoppers at the end of 3 hours*— Hamilton ( 200 ) « 
DDT at 0.75 pound per 100 gallons of water was not effective as a 
fungioide for early blight of potatoes, but controlled leafhoppers well. 
— -Heuberger (207 ) * 
A 3-percent DDT dust and a spray containing 1 pound of DDT in 100 
gallons of water were tested against standard treatments. The DDT spray 
and the dust gave control of potato leafhopper on snap and lima beans 
superior to "that obtained with pyrethrum dust. Snap beans were stunted 
for a short period after they were treated with DDT.— N. J. Agr. Expt. 
Sta. (276). 
A dust containing 5 percent of DDT and copper applied twice at the 
rate of 20 pounds per acre per application gave the highest mortality 
of insects, including the potato leafhopper, of any material tested 
(arsenical, Dithane, DH dust plus copper, sabadilla plus copper, and 
copper-lime dust) •— Munro and Redman (270) • 
Bmpoasca maligna (Walsh), the apple leafhopper 
Apple nursery stock was dusted with a 5-percent DDT dust twice dur- 
ing the season at 1-^jonth intervals. The effectiveness of this treatment 
was compared with that of 4-4-50 bordeaux mixture applied 6 times between 
June 21 and August 12, 1944. The last three bordeaux sprays were mixed 
with 3/4 pint of nicotine sulfate per 100 gallons. Both treatments con- 
trolled the leafhoppers about equally well. Meotine sulfate took fair- 
ly good care of Aphis poroi Deg. in the bordeaux blook and the aphid popula- 
tion in the DDT block dldTnot increase. This shows that some of them 
were controlled with the DOT. Since the average annual growth in the DDT 
blook measured 17*23 inches, in the bordeaux block 15*55 inches, and in 
the oontrol blook 16*05 inches, it is evident that frequent bordeaux 
application reduces, whereas dusting with DDT slightly increases the 
annual growth of young apple nursery stock.— Granovsky (18 7)* 
Apple leafhoppers were controlled with a spray of 4 pounds of 20 
percent DDT per 100 gallons of water.— Has eman (203 ) • 
DDT is very effective against apple leafhoppers.— Steiner et al. 
(334) . 
