- 16 ^ 
Twc weeks later apply .a' derris-root spra^" containing 0.01 percrnt of 
rotenone, made up according to the following formula! 100 gallons of 
watfr, 27 ounces of derris root powder containing 5 percent of rot^^none, 
■and-l pint of a good grade qf neutral mineral oil or pine oil or sulfonated 
castor oil. This derris ^pray should "be repeated 2 weeks latere Although 
dusts ha""'e not been so successful as ■ sprays in controlling the raspDorry 
ftuitworm, dusts may "be used if desired. Time of application of the dust 
mixtures should "be the same as for the sprays. The first dust application 
should consist of lead arsenate powder, mixed thoroughl2^ with an eaual weight 
of hydrated lime and applied at the rate of 35 pounds p'-r acre. The second 
and third dust applications should consist of a mixture mad? 'up of 2 pounds 
of derris-root- powder, containing approximately 5 percent of rotenone, and 
98. pounds of tobacco dust, talc, or clay as a diluent. 
Crumb (S^.) in 1935 reported results of tests at Puyallup, Wash., 
with insecticides against the raspberry fruitvrorm on Marlborough and Cuth- 
bert raspberries, loganberries, and youngberries. Best results were ob- 
tained by applying a spray consisting of U pounds of lead arsenate and U 
pounds of hydrated lime to 100 gallons of water at the peak of beetle emer- 
gence, approximotely 2 or 3 weeks prior to blossoming, follovred by a second 
application of the same spray just befot'e blossoming, with a third applica- 
i.tion of ' a derris-root-powder spray, containing 0.01 percent of rotenone, 
2 weeks after blossoming. The. omission of the first or second lead arsen- 
ate spray decreased the percentage of control. In general, sprays gave 
better results than dusts. The application of a derris-root spray con- 
taining 0.01 pf-rcent of rotenone in the third spray gave results superior 
to those obtained v/ith a nicotine sulfate spray (Uo percent of nicotine) 
l: UOO. 
The United States Bureau of Entomology and Plant quarantine (jP^) 
in, 1936 reported that large-scale tests directed against the raspberry 
fruitworm in the Puyallup Valley, Wash., shovrrd that two sprat's of lead 
arsenate applied to the plants prior to blooming, followed immediately 
aftf-r the blooming period by one spray containing derris root, gave a 
satisfactory commercial control and produced fruit frev-^ of arsenical residues 
Crumb (gU ) in I938 reported that applications of ground derri"s or 
cube root, either as a spray or as a dust, vrill give satisfactory control 
of the raspberry fruitworm, if the work is done properly. In general, how- 
ever, sprays have given better results than dusts. Three applications of 
spray containing finely ground derris or cube root powder are necessary 
for the best res^ilts. The first spray should be applied 10 days after 
blossoming begins, the second 7 days after the first, and the third 7 days 
after the second. If only tvro sprays are used, the first should be atiplied 
15 days after blossoming begins and the second 10 days later. The last 
spray, if applied later than rccomoended, may leave an unsightly residue on 
the harvested fruit, particularly if derris or cube root low in rotenone 
is used, thup making it necessary to use a large. Quantity of th^ material » 
The derris or cube powder should be made into a paste with a small Quantity 
of watrr before being added to the water in. the spray tank. The time of 
application of the dusts should be the same as that recommended for sprays, 
and 35 pounds pi r acre should be used for each application. The diluted 
spray should contain about 0.01 percent of rotenone; the dust, 0,5 pf^rcent 
of' rotenono. Very finely ground talc, bentonite clay, .and-tobacco dust 
