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Hervcy and prim ( 190 ) in 19 34 reported experimental work done in 
western New York on the control of the three common species of caul if 1 eve 
insects, including Autographa brassicac , by the use of arsenical s, dYorris 
pyrcthrum, and hellebore. Dor ris- talc dusts (0.5 and 1.0 percent rotc- 
nonc), Dercx (0.55 percent rctcnone), and dorr is-pyrc thrum dust (2.5 per- 
cent rotcnonc and 0.5 percent pyrethrins) all gave good results. The dci 
pyrcthrum mixture at the . dilutions used was very toxic to cabbage worms, 
did not appear to be superior to dcrris when used alone. In general, rat 
none was far superior to calcium arsenate against these caterpillars and 
appeared tc be about equal to or slightly better than Iced arsenate. Py- 
rcthrum was more rapid in its action against cabbage worms than rotencve, 
although the latter material appeared to have a more decided residual eff 
and gave protection to the plants over a longer period than did pyrcthrua 
Of the three species of caterpillars concerned, the imported cabbage worn 
was the easiest to control, the diamondbe.ck larvae the most difficult, 
general, the cabbage loopcr ryas not abundant enough to determine definite 
yjhat effect the materials had on it, but the degree of control obtained 
somewhat less than that of the imported cc.bbagc worm. On carl- if lever dcr 
dust should be applied at the rate of 25 cr 50 pounds p;r acre. During t 
season of 1933, with moderate infestation, two applications about three t; 
apart gave adequate protection, 
Rcid (3_44) in 1934 reported that at Charleston, 3. C,, dcrris-root 
powder continued to prove toxic to the cabbage worms present, including 
loopcrs. The degree of control obtained with dcrris powder was proportio 
ate to the strength of material used. Best results followed the use of a 
mixture containing 1,5 percent of rotenouc. An increase in this concen- 
tration to as high as 3.4 percent in 1933 did not apparently increase the 
kill. A mixture containing only 0.1 percent of rotcnonc shoved some toxi 
ity. Rcid (346) in 1938 summarized results obtained in tests directed 
against cabbage worms on cabbage grown at Charleston during the fall and 
winter of 1937-38. He reported that a populaticn consisting of the ce.b- 
bagc loopcr and various ^grotinac could be controlled effectively by the 
use of a dust consisting of calcium arsenate and hydrated-limc mixture 
(3:1) prior to the heading of the plants, followed by applications of a 
pyrcthrum- talc-dust mixture (0.3 percent total pyrethrins) or a dcrris- 
clay-dust mixture (1,0 percent rotcnonc) at 10-day intervals after the 
plants had headed; provided the plants had been well protected against 
cabbage voms before being thinned or transplanted. The pyrcthrum-dust 
mixture and the dcrris-dust mixture were most effective against the c'dobaj 
loopcr, and the calcium arsenatc-dust mixture effective against the 
Agrotinac. These results wore also referred to by the Unitod States Dcpaj 
ment of Agriculture, Bureau of Entomologv and Plant Quarantine (445) in 
1938. 
Rcid and Bare (347) in 1938 reported that against the cabbage loopcr 
the 1-pcrccnt rotcnonc and the dorris-pyrcthrum-dust mixture (0,5 percent 
rotcnonc plus 0,2 pcrcont pyrcthrins) applied at 7-day intervals wcro vaosj 
effective. 
Huckctb ( 201 ) in 1934 reported field toots on Long Island with dcrris 
for the control of cabbage worms. The materials used consisted of propria) 
products appliod, so far as possible, according to the directions on 
go. Tho infestation was largoly due to Pioris rapac (L.), althod 
oon advanced from June to July, klutel la macul ipenni s (Curt.) aa 
Autographa brassicao became increasingly numerous, Applications were uadd 
