6 UAL REPORTS OF DEPARTMENT OF AGRICULTURE, 1939 
Bprayer in controlling the grape leafhopper. This outfit delivers the 
icide by means of a blast of steam requiring comparatively little 
water. The kill of the insects was definitely inferior to that obtained 
with ilif standard power machine. As the quantity of materia] deliv- 
ered was increased, the control also increased, but the results did not 
obtained with the standard power sprayer. 
NUT INSECTS 
The hickory shuck worm on pecan was found by the Albany, Gra., 
laboratory to have in part a 2-year life cycle. Fifteen pe 1 one 
lot of materia] that entered hibernation as larvae in 1936 appeared as 
moths during the second season. This 2-year cycle will enable the 
insect to bridge over years when a crop of nuts is not available for 
them. The insect breeds in phylloxera galls before pecan nuts have 
formed, and develops more rapidly in these galls than it doe.- in pecan 
nuts. In field experiments nicotine sulfate, nicotine-bentonite, and 
phenothiazine did not give sat isfactory control of this insect 
At Monticello, Fla., a single application of a commercial nicotine- 
bentonite mixture with summer-oil emulsion apparently reduced an 
infestation of pecan nm casebearers 69 percent, and a second applica- 
tion gave a control of 81 percent. Field applicat ions of certain of I he 
tar-oil distillates during the dormant period showed reductions in the 
population of nut casebearers in the first generation ranging from 37 
percent for a 3-percent mixture up to 93 percent reduction for a 
<;-., -percent mixture. 
At Brownwood, Tex., it was found that the nut casebearer feeds 
extensively on the pecan buds and shoots before turning its attention to 
the nuts, indicating the necessity for spraying the buds and shoots as 
well as the nuts. In Florida a number of individuals were reared from 
eggs t<> adults on shoots and leaves. This offers a possible explanation 
of the occasional occurrence of severe infestations followim: yen: 
nut-crop failure. 
Experimental work in Texas during 1938 indicated that the prob- 
lem of borers in the wounds caused by grafting improved variet 
pecans on native trees was materially aided by the inlay bark graft 
and the improved grafting waxes developed by the Bureau of Plant 
Industry. This method results in less borer infestation than the 
method of top working which has been in general use in Texas. The 
use of paradichlorobenzene in the grafting wax at the time the top 
working was done seemed to have no value in borer control. After 
infestation had taken place, however, the use of additional wax impreg- 
nated witli paradichlorobenzene was found effective. 
The survey work on filbert insects was continued by workers sta- 
; ioned at i he Eugene, ( )reg., laboratory. The so-called ( -atalina cherry 
moth (Melu8opu8 latiferreanus Wals.) , an important filbert pest, has 
found to range in distribution from the Canadian border in Wash- 
ington to Los Angeles County in southern California. Although the 
Catalina cherry moth is known to i\^*\ on a number of different plants, 
the survey thus far lias revealed it in the Northwest only on filbert, 
hazel, and oak-. In southern California it was reared from oak galls 
and from the fruit of the Catalina clierrv. 
