- 53 - 
control of those cabbage worms, while dusts of weaker concent rations of 
rotcnonc and pyrcthrins wore less effective. Derris and cube dusts having 
approximately the same rotcnonc and total ether extractive content appeared 
to be about equally effective for the control of those posts. 
Van Gundia (447) in 1936 reported that control of the Japanese beetle 
with applications of rotenono dust, made from oithur cube or derris, was un- 
satisfactory. "Wo are not particularly intorostcd in killing thorn by contact 
whero the foliage is sacrificed, but wo are interested in keeping them array 
from those treated plants. We arc quite confident that something can be 
worked out to accomplish this." 
LoPolloy and Sullivan (260) in 1936 reported a study of the toxicity 
of rotenono and pyrcthrins, alone and in combination, to houscflios, when 
tested by the turntable method. A sample of foliage of Tephrosia vogclii was 
about one-fifth as effective as commercial samples of derris and cube. 
The New Jersey Agricultural Experiment Station (303) in its 1936 
annual report (published in 1937) reported that the discovery that insect 
toxication by cube is apparently identical with insect toxication by derris, 
provided the component toxic qualities are the same, is a matter of groat 
importance bocauso the price of derris has boon skyrocketing, while the 
prico of cube has remainod much more stable. 
The New York Agricultural Experiment Station at Cornell University 
(307) in its 1936 annual report (publishod in 1937) reported that rotenone 
added to naphthaleno-talc dust slightly increased the effectiveness of this 
treated against onion thrips. Rotenono dust used undiluted was not 
satisfactory as a control for onion thrips. Ground derris root and cube root 
as sources of rotenono in sprays controlled the immature stages, but they 
were not so effective against the adults. There were no noticeable differences 
in the effectiveness of these two sources of rotenone. 
Against the hairy chinch bugs attacking lawns, nicotine sulfate, 
both as a spray and as a dust, has proved effective. Rotcnonc and tobacco 
dust also have given effective control in experimental work. 
Lettuce yellows caused considerable losses to lettuce growers on Staten ' 
Island in 1935. Tests proved that the method of control by barriers afforded 
some reduction in the disease. Dusts containing sulfur, pyrethrum, and 
rotenone reduced the amount of yellows in experimental plots, through the 
control of leaf -hoppers which spread the disease. 
Growers were supplied with full and timely information regarding the 
use of rotenone and pyrethrum insecticides to avoid objectionable residue 
on such crops as string beans, cauliflower, and market cabbage. 
The Colcrado Agricultural Experiment Station (38) in its 1936-1937 
annual report reported that rotenono was found superior to pyrcthrins 
in controlling the imported -cabbage worm; 2.84 pounds of rotenono dust 
per acre gave a significant kill. The tests of tho season failed to give 
a satisfactory control of cabbage loopers. The diamondback moth larvae 
rank about midway between the imported cabbage worm and the cabbage locper 
in resistance to pyrcthrins and rotenono. 
