ENTOMOLOGY AND PLANT QUARANTINE 
5 
NUT INSECTS 
A new laboratory was established in the spring of 1987 at Monticello, Fla., 
in cooperation with the Florida Agricultural E^xperiuient Station for a study 
of pecan insects. At the outset special attention is being directed to the con- 
trol of the pecan nut casebearer. The results obtained in the control of this 
insect in the spring of 1937 by the use of nicotine sulphate in combination 
with white oil emulsion were in line with those previouslj' reported by the 
Albany, Ga., laboratory. That laboratory is now giving all of its attention 
to the hickory shuckworm on pecan, for the control of which adequate meas- 
ures are not yet available. Special emphasis is to be placed on the relation of 
natural enemies to the control of this insect and to possible cultural methods 
of controlling it. 
In experiments with the obscure scale in northern Louisiana it was learned 
that oil sprays have an important residual effect which is not evident until 
the female scales reach maturity. In orchards sprayed with 2- or 3-percent 
lubricating-oil emulsions during February and March, only from 1.3 to 9.5 
percent of the females that reached the appearance of maturity were able to 
lay eggs, whereas in unsprayed trees in the same orchards, 6H to 86 percent 
of the mature female scales laid eggs in a normal manner. This means that 
it is possible to obtain satisfactory control of the obscure scale in pecan 
orchards with low strengths of oil emulsion, which is fortunate in view of 
the susceptibility of pecan trees to injury by oil sprays. 
The use of lead arsenate as a spray at a strength of 3 pounds in 100 gallons 
of water, with 3 pounds of hydrated lime, has given very effective protection 
of young pecan trees from attack by the adult May beetles of the genus 
Phyllophaga in northern Louisiana. In most cases four or five applications 
were made at frequent intervals, but it is believed that the beetles should be 
well controlled by three applications put on during the early part of their 
feeding period. Observations have indicated that most of the protection results 
from a repellent action on the part of the spray. A little foliage injury de- 
veloped from five applications, but this was not at all serious, 
DRIED-FRUIT INSECTS 
The motor-driven raisin cleaner developed by the Fresno, Calif., laboratory 
in 1935 was further improved, and it appears to be particularly effective in 
removing infestation of the raisin moth from Sultanina (Thompson Seedless) 
raisins, reducing the numbers of the insects in many cases more than 90 percent, 
and in addition removing most of the sand and debris. The paper trays on 
which the raisins are now extensively dried prevent infestation to a certain ex- 
tent, and by the use of the paper trays, the cleaning machine, and shade-cloth 
covers over the boxes of raisins while temporarily stored on the ranch, the 
delivery of comparatively clean raisins now appears possible. Dried pears 
practically free from infestation were obtained by covering the fruit with cloth 
during the final stages of drying, confirming the results of previous experiments 
with various dried fruits. In Arizona, cotton-cloth extensions on the paper rain 
covers used for dates gave promise of success in the exclusion of certain in- 
sects that have been attacking dates in the final stages of ripening or drying 
while still on the tree. 
The practical utilization of cotton cloth for the prevention of insect infesta- 
tion of dried fruits while being held in stacked trays on the ranches is being 
stimulated by a cooperative project carried on by the Agricultural Exten.sion 
Service of the University of California. For this work about 20.000 yards of 
cotton cloth have been furnished by the Agricultural Adjustment Administration 
as a part of a cotton-diversion program. This is being distributed to repre- 
sentative growers, and detailed records will be kept of the results. 
In addition to the mulberry, which in most localities is practically the only 
food available to the raisin moth in the spring during the first generation, 
Mission figs were found in one locality to be of considerable importance in the 
building up of the raisin moth ])opulation e.nrly in the season. For the first 
lime serious injury by larvae of the raisin moth to fresh grapes on the vines 
was observed. 
SUBTROPICAL FRUIT INSECTS 
Field experiments to determine the effect on the trees of tartar emetic when 
used as a bait spray on citrus trees have been continued by the Orlando, Fla., 
laboratory, in cooperation with other bureaus. Plots of trees have been sprayed 
