BUREAU OF ENTOMOLOGY .VXD PLANT QUABANT] 5 
PEACH INSECTS 
Data obtained on the parasites of the oriental fruit moth at Moores- 
town, X. J., definitely support the prevalent impression that high 
parasitization of the larvae of the twig-infesting broods is a most 
important factor in reducing subsequent fruit infestation in mid- 
season varieties of peaches. In three groups of orchards in which 77, 
63. and 51 percent of the twig-infested larvae were parasitized, the 
harvested fruit was infested 4, 15. and 30 percent, respectively. ?. j 
liberation experiments associated with this work indicated that early 
season parasitization can be substantially increased by the liberation 
of comparatively small numbers of parasites. 
Recovery collections, in cooperation with State agencies, were con- 
tinued as during previous years. The more significant features result- 
ing from this work were that parasitization, particularly of the first 
brood, increased over any previous year; that the parasitization by 
Macrocentrus ancylivorus Roh. is still increasing: and that the para- 
sitization immediately after the release of Bassus diversus Mues. did 
not increase to so great an extent as in the case of Inareolata molestae 
(Uchida). 
Ethylene dichloride emulsion has continued to give effective control 
of the peach borer with little or no injury to peach trees, in work 
carried on chiefly near Fort Valley, Ga. Since ethylene dichloride is 
effective at low temperatures, it can be used both earlier and later in 
the season than paradichlorobenzene, which requires moderately high 
soil temperatures for satisfactory results. Because it is easy to apply 
and is comparatively safe, this material is being rapidly adopted by 
commercial growers. 
In laboratory experiments with the plum curculio conducted during 
1938 at Fort Valley. Ga., solutions of dichloroethyl ether gave almost 
complete kills of the insect in the soil. Similar results were obtained 
in experiments carried on in cages over peach treees where 1,000 
curculio larvae were placed in the soil under each cage. At the 
strengths used, the treatment caused no apparent injury to the trees. 
The work to determine the insects responsible for the transmission 
of the phony peach disease and peach mosiac has been continued. The 
surveys carried on with trailer laboratories have indicated a number of 
insects that there is reason to suspect may be the transmitting agents 
of these diseases, and this has made necessary the establishment of fixed 
laboratories to study the host-plant relationships and to conduct trans- 
mission experiments with these suspected insects. This work is being 
carried on at East Chattanooga, Tenn., at San Bernardino. Calif., and 
at Brownwood, Tex., in cooperation with the Division of Domestic 
Plant Quarantines and the Bureau of Plant Industry. 
GRAPE INSECTS 
An all-season treatment with phenothiazine gave a high degree of 
control of the grape berry moth at Sandusky, Ohio, under conditions of 
extreme!}' heavy berry moth concentration on a very light crop of 
grapes. 
In cooperation with the Bureau of Agricultural Ch< and En- 
gineering, experiments were carried O] the value of a vaporizing 
