-56- 
Treatment Leafworm 
control 
Percent 
Cube (4 percent rotencne) 77 
Derris (4 percent rotenone) , 78 
Tephrosia virginiana root 
(1.7 percent rotenone) 46 
Commercial calcium arsenate 89 
The Division of Cotton Insect Investigations of the United States 
Department of Agriculture, in a memorandum to R. C. Roark, reported the 
following results of tests at Tallulah, La. , and Port Lavaca, Tex. in 1936: 
Leaf worm 
m ortality 
Treatment Percent 
Derris 40 percent, sulfur 60 percent 
(rotenone 1.6 percent) 63.5 
Derris 20 percent, 'sulfur 80 percent 
(rotenone 0.8 percent) 55.7 
Derris 10 percent, sulfur 90 percent 
(rotencne 0.4 percent) 41.1 
Derris (rotenone 4 percent) 77.7 
Calcium arsenate 89.14 
Check 3.37 
Smith and Scales ( 377 ) in 1937 reported that calcium arsenate either 
used alone or in mixtures with sulfur, caused a higher mortal ity of leaf- 
worms than did derris, cube, or devil 's-shoestrings when tested in cages. 
Results were as follov^s: 
Treatment Control 
Percent 
Calcium arsenate 89 
Derris (4 percent rotenone) 77 
Cube (5 percent rotenone) 76 
Devil ' s-shoestr~ ; ngs (1,7 
percent rotenone) 44 
Pyrethrum (0.76 percent 
pyrethrins) 92 
