BUREAU OF ENTOMOLOGY AND PLANT QUARANTINE 5 
Ten shipments of parasitized material from Japan, received in the summer of 
1935, yielded 31,384 parasites belonging to 14 different species. Thirteen of 
these species were liberated in 103 colonies in important peach-growing districts 
in 7 Eastern States. In addition, 10 colonies of native species were liberated in 
2 States where they were not already established. Recovery collections have 
been made, in many cases with the cooperation of State agencies, in 16 States 
where parasites had been liberated before. 
Field experiments in 1935 in control of the peach borer confirmed earlier 
favorable results with emulsions of cottonseed oil impregnated with paradi- 
chlorobenzene. An emulsion of ethylene dichloride gave even better control of 
this borer without injury to the trees and at a somewhat lower cost. Studies of 
the biology of the peach borer have indicated that in Georgia a small percentage 
of the population produces a second generation the same year, and that a few of 
the moths continue to deposit eggs later than was formerly thought. 
With the plum curculio, experiments in the 1936 season are being carried on 
with ground derris root and with schedules calling for the use of fluorine com- 
pounds in part of the spray program and lead arsenate in the rest, in the hope of 
avoiding injury by the fluorine compounds and excessive poisonous residues. 
In experiments in the winter of 1935-36 five different blended oils gave 
approximately as good control of the San Jose scale as straight-run oils of 
similar specifications used at the same strengths. Oils having volatilities of 8 
to 12 percent were definitely less effective in scale control than otherwise similar 
oils having volatilities below 5 percent. 
GRAPE INSECTS 
Phenothiazine gave a fair degree of control of the grape berry moth, but caused 
considerable russeting on some of the grape clusters. This injury may have been 
due in part to the use of fish oil with the phenothiazine. Slight foliage injury 
developed on the vines sprayed with phenothiazine with fish oil but no injury 
where the phenothiazine was used alone. Several calcium arsenates, prepared 
according to definite specifications, gave a fair degree of control. Nicotine 
bentonite, in the 1935 experiments, seemed inferior to arsenicals in control of 
the berry moth. 
In connection with the destruction of hibernating grape leaf hoppers (Ery- 
tlironeura comes Say and related forms) in their winter quarters near the vine- 
yards, it has been noticed that the hoppers are attracted in large numbers, and 
sometimes for considerable distances, to pomace heaps from wine presses located 
near the vineyards, the insects then hibernating in the pomace and in trash and 
weeds nearby. The burning over of pomace heaps and surrounding areas 
destroyed great numbers of the insects. 
In connection with field experiments carried on with various materials pri- 
marily for the control of the grape berry moth, observations are being made on 
the effect of these materials on the beetles of the grape rootworm. Calcium 
arsenate and lead arsenate continue to hold the infestations at a minimum. 
Certain of the nonarsenical materials, particularly those including nicotine and 
pyrethrum, appear to have little effect on adults of the grape rootworm. 
NUT INSECTS 
Experiments in 1935 carried on by the Albany, Ga., station gave further proof 
of the effectiveness of late-spring spraying with nicotine sulphate combined with 
summer oil emulsion or with fish oil in the control of the pecan nnt casebearer, 
although the average control resulting was only 75 to 85 percent, as compared 
with better than 90 percent in previous years. The use of nicotine with bordeaux 
mixture gave results nearly as satisfactory. In the Brownwood, Tex., district 
nicotine sulphate with oil gave reductions in infestation averaging 95 percent. 
In that area iead arsenate has continued to give effective control and appears 
to be fairly safe on pecan foliage. 
Further experiments have been carried on with bordeaux mixture as a correc- 
tive for injury by calcium arsenate, which is used in summer sprays for the 
control of the pecan casebearer. Bordeaux mixture at a strength as Low as 
lV^-50 was satisfactory in preventing injury to the foliage by calcium arsenate, 
but the application Of a concentration even as low as this was followed by an 
increase in infestation by the black pecan aphid. 
Work was carried on in L935 to determine the extent to which the hickory 
shuckworm may he controlled in pecan plantations by plowing under the shucks. 
