^ 87 - 
Troatmcnt Control 
Pnrcont 
Ovibc. Uo Torrcent, sulfur 6o percent 
(rotonone I.96 porccnt) ^5 
Cube 20 percent, sulfur 80 percent 
(rotononc 0.98 porcc'nt) 28 
Cub" 10. percent, sulfur 90 percent 
(rctenono O.49 psrc-nt) 6 
Cube 10 percrnt, pyrrthrum 10 percent 
sulfur 80 percent (rotonon- O.U9 
percent) 9 
Cube (rotpnone U.9 percent) 80 
Derris (rbt"none 3*9 percent) 67 
Devil' s-shocstrings (rotenone I.7 
percent) 26 
C?ilciuni ?irs-'"n''.tc 73 
Young' ^'>nd S-nith ( U19 ) in I936 report^-d the result? of fi-ld-pl^et 
p.nd c^ge testr; for boll woovil control. Derris dusts wcr.-^ mede by mix- 
ing derris powder, contrin'ing U percent of rotenono^ vith flour or with 
kaolin to rotenone contents of 2, 1, and 0.5 pfrcf-nt. In c-ges tho boll 
weevil mortality observed nt T^^llul^.h, Le., in IQ3U was a^ follows: 
Trcptmciit Avornge Hort-'lity 
Fercrnt 
Calcium arsenate 81.8 
Derris dust (2 percent rotenone). 72-9 
Derris dust .(l percent rot.-none) 52.6 
Derris dust (0.5 TJercent rotenone) U2.5 
Untre-oted 32.8 
The authcrr concluded •?.? follov/s; 
Derris-root dust mixtures conteining 0.5, 1, ^'•nd 2 
prrcent of rotenone, bnsed on the souare in'festption -nd 
yield records, gnvr very little ^ if any, weevil, control. 
The fnilure of thr plrts treated vith derris-reot dust in 
two tests to yielr oc, v/ell cs the untrc^^ted plats indic?^tes 
thnt the derris-root dust mixtures, when us.c'd at the rate 
of Ij to 6 pounds per Bcre, had no v^lue as a means of boll 
we-^vil control. The results with derris in cage, tests do 
not agrr,- vrith the result"! in fi-^ld-plat- tests. The higher 
boll wevil kill in the c^ges vas probf>bly 'due to the f^ct 
that the boll we<~"'ils were stupefied shortly after the ppplic- 
^tions of derris-root mixtures vrere inade and vro'ulr fall to the 
c-^gr bottoms. whTf the." \^y eyposfd to the sun and were 
killrd befor th.-y rrcovr^d from the effects of thr derris. 
Th- Division of Cotton Insect Investig-nions, United States 
Bureau of Entonology 9nd Plant Quarantine, in a memorandum to the 
chief of the Bureau, d-^ted December 2, 1^36, reported the following 
rep-ilts of tests made at Tallulah, L^., and Port I^avaca, Tex., durin^: 
1936: 
