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HERBERT, F. B. (2248) 
1931. HISTORY OF THE OIL AND NICOTINE COMBINATION. Jour. Econ. Ent. 24: 
991-997. 
This is mostly a discussion of the literature on the subject. 
The following is a list of the insects which can he controlled "by a 
combination of oil and nicotine (p. 995): aphids, mealybugs, thrips, 
whiteflies, psyllids, lacebugs, scale insects, leafhoppers, treehoppers, 
redbugs, cabbage bugs, plant bugs, spittle bugs, casebearers, red spiders, 
rust mites, blister mites, sawfly larvae, midges, fleas, chicken lice, 
leaf roller eggs and larvae, canker worms', caterpillars, bud moths, twig 
borer larvae and cranberry fireworm. 
HERRI OK, G. W. (2249) 
1931. SOME SHADE-TREE PESTS AND THEIR CONTROL. N. Y. (Cornell) Agr. 
Sxpt. Sta. Bull. 515, 26 pr)., illus. [Abstract in Rev. Aopl. Ent. (A) 
19: 435. 1931.] 
A nicotine and oil spray already noticed [Rev. Appl. Ent. (A) 14: 
477], applied during the first week in July, will control Chionaspis 
pinifoliae Fitch on pines and spruces. Experiments have shown that the 
spruce gall aphid ( Chermes abietis L. ) is destroyed by lime-sulphur, 
miscible oils, or nicotine sulphate (1:400) with 6 lb. powdered soap to 
100 gal. applied in April. 
PETROV, A. D., ET AL. (2250) 
1931. THE "CONTACT" AS ACTIVATOR OF CONTACT INSECTICIDES. Bull, plant 
Protect. 3 (l): 183-187, illus. [in Russian; Abstract in Rev. Appl. 
Ent. (A) 20: 199-200. 1932.] 
Since hundreds of tons of nicotine sulphate, with soft soap as 
a spreader, are used yearly in the Russian Union in sprays against 
insect pests, an attempt was made to find a product manufactured in 
the country with an action similar to that of Inman's "activator", 
the addition of which to the sprays would permit a decrease in the 
concentration of nicotine and the exclusion of the expensive soft 
soap. Two such products are described. The first is a solar oil 
activator and the other is called "Contact". The latter contains 
40 percent sulpho-acids and 15 percent oil. 
TJhen U3ed against aphids, nicotine sulphate at 1 to 4,000 with 
0.5 percent "Contact" gave much better results than at 5 times this 
strength in combination with soap and soft water. Nicotine sulphate at 
1 to 4,000 with 0.5 percent of the solar oil activator gave slightly 
poorer results than at a concentration of 1 to 800 with soap and rain 
water, but was considerably more effective than at the latter concen- 
tration with casein and hard water. 
