- 93 - 
A mixture of rotonone (.dc^ripl 1 pnrt ani sulfur 9 parts, applied 
as a dust, grve as good control of ' the strawberry weevil as the standard 
treat-ient of line-calcium a.rsenate "but injury to the plants resulted. 
The experience seems to be that sulfur treatments may be safe in some 
reasons but {?Angerou« in others. Pyrcthrun proved inferior to the rote- 
none-sulfur or the linf^-calciur". arsenate treatments. In gen-ral, growers 
do not make applications frequently enough. Dusts are removed by rains 
and more freauei-.t applications are needed in rainy seasons. Satisfactory 
re.sults may be expected only where a good coverage is maintained through- 
out the da.nger period, — Few York County Agents' Training School ( 29^ ) in 
193s. 
Derris (U percent of rotenone) at U pounds per 100 gallons of spray 
proved somewhat less effective tha.n cryolite spray or 85^15 ^lusts of 
sulfur with either lead arsenate or calcium arsenate. — Stearns ( 3^3 ) in 
1937. 
Amos and Pierpont (_ll) in 1939 report 'd the results of dusting 
cxTDPriments for control of the strawberry weevil in Dola.ware, G-round 
derris root containi:ig U perc^^nt of rotenone vjas added to a mixtiire of 
inert clay, ^ parts, and Celite, 1 part, to make .dusts containing 0.5, 
1.0 or 1.5 percent of rotenone. Results vrere as follov/st 
Rate 
Incre; 
ase in uninsured 
per 
Buds 
buds 
over untreated 
Treatment 
acre 
cut 
check 
?on.n:\<3 
POTCrnt 
Percent 
Inert clay + Celite U:l 
25 
Rp; 
11 
Inert clay + Celite ^:1 + 
0.5 percent rotenone 
2? 
^7 
2k 
Inert clay + Celite U:l + 
1,0 percent rotenone 
25 
72 
50 
Inert clay + Celite U:l + 
1,5 percent rotenone 
30 
28 
55 
Lead arsenate-srlfur 1:5 
30 
^1 
2k 
Untreated check 
62 
— 
Haude ( I8I ) in 1939 recommended du-^ting with culie or derris plus 
sulf-r. 
Anthonomus vcstitus Boh,, the Peruvian boll vrcevil 
Wille, Ocniapo, Weberbauer, and Schofield ( U15 ) of the Agricultural 
Experiment Station at La Molina, Pfru, in 193? reported that dusts of 
ground cube root cf 5 "-nd 1 percent rotenone contents gave 50 and I5 
percent mort^^lity, respecti^'ely, of --adults of this sDCcies in the labora- 
tory, 
Anthonomus sp. 
The Wageningen Plantenziektenkundige Dienst ( U02 ) 'in 197"^ reported a 
derris powder (2 percent of rotenone) at 1^50 in a l-porcent-soap solution 
to be ineffecti'-o ag'^inst Anthonomus on str^^wborriea.' 
