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Stpcr ( 336 ) in I932 rr-ported favcrabl • repnlt?^ on the control 
of the raspberry and loganberry bci tie in England by means of derris. 
This beetle was fonerlr controlled by three applications of lead 
arsenate given when one-third, two-thirds, and all the blossoms were 
fully open. On accoiint of arsenical residue on the ripe fruit vrhen 
the young berries were sprayed vrith lead arsenate, this insecticide 
was abandoned in favrr of derris. In 1928 ?>, single aprilication of 
derris spray reduced the infestation considerably. In I929 indifferent 
results were obtained because the derris used ha.d bfTn in stocV: for a 
long time. In I93I two sprayings of derris reduced the average infest- 
ation of loganberries fro^ 66.3 to lU,6 percent and of raspberries from 
78.3 to 5.6 percent. On loganberries this treatment nearly doubled the 
totfil weight of the crop and increased the proportion of mar^ce table fruit 
in a badly infested plantation from 23.? to 77«7 percent. This meant an 
increase in marketable fruit at the rate of over 2 tons (from 8.3 to 
51.8 cwt.) per acre. The average number of loganberries p' r pound of 
ripe fruit over the whole of the picking season worked out at I76 on 
unspra.yed and 127 en sprayed plets, A derris preparation containing 
soap was used <^.t the rate of 5 pounds per 100 imperial gallons of 
water and the spray was applied at the rate of 500 gallons p''r acre 
per application. 
The Agricultural and Horticultural Research Station of the Uni- 
versit.' of Bristol (^) , England, at Long Ashton, in 1933 stated tha.t 
efficient control of the raspberry and loganberry beetle is obtained 
with derris-soap suspensions. 
Hus (209 ) in 1933 stated that derris preparations used as spr?iys 
kill newly emerged larvae of the raspberry beetle. 
Kearns and Walton (2U2) in 193"^ reported experiments with pyreth- 
rum and derris washes and dusts for the control of the loganberry and 
raspberry beetle. Tests are recorded with a derris wash (2-l/2 or 5 
pounds of derris powder cont?in-ing 1,72 percent rotenone and 10 pounds 
spraying soap per 100 imperial gallons), derris emulsion (derris extract 
in rape oil), and derris dust (containing 10 percent derris and 0.18 
percent rotenone). The proprietary derris emulsion gave very DOor results 
against Byturus . Two applications of a derris w??sh containing less th?)n 
0,00U percent of rotenone gave a high control of the larvae. The first 
application' was made 10 days after about one-third of the flower buds had 
opened and a second application 10 days after the full flowering period. 
No further increase in control resulted oy using a wash of a higher con- 
centration than O.OOU percent of rotenone. In seasons in which the beetles 
cluster in large numbers on the unopened end ,iust-rpening flower buds, 
the application of a derris dust (containing 0,18 percent rotenone) Is 
effective in killing large numbers of them. The dusting should be followed 
by at least one applic-tion of f> derris wash, to kill the larvae. 
Kearns and Walton ( 2U3 ) in 193^ furth r compared the relnti"e 
effici'-ncy of pyrethrum and derris for the control of B, trmentosus . 
A plot of raspberries of the variety Lloyd George wr>s p'^.iacent to the 
Baumforth 'A' raspberries. One portion was sisr^yed twice with the 
1.0-percent-pyrethrum emulsi-^n and mother portion with a dorris-soar' 
wash at periods calculated to kill the larvae. 
