Q ANM AL KKI'OUTS (JK DKI'AKT.MKNT OF AGKICULT UKK. 1037 
;it lO-day to 2()-(l;iy intcrxals with mist sprays (•oiitaiuing 4 ik)U1k1s of tartar 
('luetic and 5 gallons of molas-ses in 1(X) gallons of spray. By the end of June 
Vj'67 certain ui these trees had rcM.eived ijU successive applications. Careful 
measurements of trunks, branches, leaves, and fruit made hy workers of the 
Bureau of Plant Industry revealed no injurious effects, and the analyses of juice 
samples made Ity the Bureau of Chemistry and Soils showed no differences in 
(juality that could be attributed to the use of the spray. 
Much attention has been given to the develoiiment of a standardized pro- 
cedure for labcu'atory exiM-rimcntation with the California red scale in order 
to overcome tlu> extreme variability which has thus far been evident in the 
results of experimental work. In some cases in the past the mortality of 
scales on individual lemons fumigated at the same time has ranged from 5(1 
to 100 percent. Dehnite p'rogre.ss is being made toward the development of 
methods that will overcome this variability, giving more consistent results 
that can .sjifely he used for drawing conclusions. 
Populati()ns of the California red .scale derived from areas where they are 
said to be resistant and other i opulal ions from areas where they are .'^aid to ]>e 
nonresistant to cyanide fumigation hav(» been maintained under i«lenti(al con- 
ditions in the insectary at the Whittier laboratory, but completely isolated 
from each other. Periodic fumigations are being made to determine the rela- 
tive susceptibility of the different strains. Preliminary results indicate that, 
a year after the establishment of the strains in the in.^ectary, the initial 
differences in susceptibility still exist. 
Studies of the biology of the California red scale have given more accurate 
information on reproducti(»n than has hitherto been avaihible. The greatest 
number of young produced by a single female was One scale produced 
young over a period of 287 days. Because of this long period of reproduction, 
the generations of the scale insect overlap to a considerable extent. 
JAPANESE AND ASIATIC BEETLES 
In the oUUr areas of infestation the emergence of adult .Japanese beetles 
began somewhat earlier in 19o6 than in 11)35 but did not reach a peak so 
quickly. There was a general increase of beetle abundanc-e within the New 
York, N. Y., metropolitan area, and a continuance of large areas of severe 
injury in north-central New Jersey, eastern Pennsylvania, and, to a modified 
extent, in southwestern New Jer.sey, with the development of very serious 
injury in northern Delaware, northeastern .Maryland, and extreme southeastern 
Pennsylvania. In .southern New England the population showed a definite 
increase in 1986 as coini)ared with 1J)35. There was. on the other hand, a gen- 
eral decrease in injury in the older infested area in the general vicinity of 
Phihidelphia. perhaps in part due to severe mortality in certain localities 
during the winter of 1935-3G. 
As bait materials for the adult beetles, certain grades of Ceylon and Java 
citronella oil appeared to be more attractive to the beetles than the grade of 
geraniol used as a check bait. This held true in various tyiH's of traps ;ind 
disp<'nsers. Citronella oil is cheaper than geraniol and appears to be a sati.s- 
fatory substitute attractant for the beetle. 
Further imi>rovements have been made in the rosin-residue emulsion as a 
sticker for use with (l(>rris, which is the most promising substitute for lead 
ar.senate as a repellent for the beetle. Out of a large number of materinls 
used with derris in an etTort to (l(H*rease the rate (»f its decomposition by light 
or its removal by rains, tho.se which caus(>d the derris to be nuxst iM-rsistent 
reduced at the same time its value as a r«>pellent. with the exception of sulpliur, 
which appeared to increase its value. I'Meld exi)erini(Mits with derris and rosin- 
residue enudsion. and with lime and aluminiuu sulphate now recommended for 
the i)rf)tection of early-ripening tree fruits, contiruied i)revious results and 
support existing recommendations. 
Various materials have hovn tested to determine their influence on the 
<'ffecti veil ess of lead arsenate in (he control of larvue in the soil. The pbos- 
pliates of sodium. i)otassium. or aninioiiium signiticantly increased the solu- 
bility of lead arsenate in the soil, ami the phosphates of i>ot:issiuni and sodium 
also Increased its insect icida I acti<»n when the lead arsenate was used at dosages 
of h'ss than 1.<XK> pounds per acre, conflrniiug results of the previous year. 
The i»hospIiafes of calcium, on the othiM* baiMl. increas(»d neither the solubility 
of tlie lead arsenate nor its toxicity to th(> grubs. The addition up to 10,»X)0 
