cure nearly all cases of streptococcal staphylococci. They should lead to 

 mastitis. The aureomycin also ap- better methods of diagnosis and con- 

 pears to be highly promising for the trol of mastitis caused by these bac- 

 treatment of staphylococcal mastitis. teria. 



Studies are being conducted on the L. W. Slanetz, F. E. Allen, 



types and pathogenicity of mastitis AND Ralston Read 



Entomology 



The European Corn Borer Can Be 

 Successfully Curtailed with DDT. 

 Results of experiments carried on for 

 the past three years in Somersworth 

 and Pittsfield, show that the Euro- 

 pean corn borer can be controlled 

 satisfactorily with DDT dusts. The 

 tests involved both market sweet 

 corn and canning corn. 



It was found that four applications 

 of a 3 per cent DDT dust gave the 

 best results, over 90 per cent of the 

 ears being borer-free. Three appli- 

 cations of the DDT dust gave slight- 

 ly less than 90 per cent borer-free 

 ears. Control with fewer applica- 

 tions was unsatisfactory. The dust 

 was applied at the average rate of 

 35 lbs. per acre. This is the equiva- 

 lent of approximately 1 pound of 

 actual DDT per acre. 



Liquid sprays of DDT in oil also 

 were tested. Four applications of 

 DDT oil solution gave approximately 

 85 per cent borer-free ears. 



J. ,G. CoNKLiN, R. L. Blickle, 

 and W. J. Morse 



New Insecticides Have Many Uses. 

 The application of parathion in the 

 calyx, and first and second cover 

 sprays appears to have given good 

 control of the red-banded leafroller 

 on apples. Some injury to the foli- 

 age has occurred with the calyx ap- 

 plication. Rhothane wettable pow- 

 der, Rhothane emulsion, and two 

 new compounds. No. 118 and No. 

 1189, also gave rather promising re- 

 sults against the first brood of the 

 leafroller without causing any ap- 

 parent injury to the foliage of young 

 fruit. 



Parathion at the rate of IV2 ^^bs. 

 of 15 per cent wettable powder has 

 given satisfactory control of the eye- 

 spotted budmoth in commercial or- 

 chards. 



Limited tests with a new miticide 

 known as Arathane are being made 

 during the current season. The ma- 

 terial may have promise in control 

 of orchard mites and mites infesting 

 vegetable and ornamental crops. 



J. G. Conklin, R. L. Blickle, 

 and W. J. Morse 



Better bisect Control with Nico- 

 tine Sprays. Certain chemical com- 

 pounds, when added to nicotine 

 sprays, will increase the kill and thus 

 result in better insect control. This 

 year, 165 compounds have been 

 tested. Of this number 25 com- 

 pounds were found to increase the 

 toxicity of nicotine sprays when used 

 against aphids. These materials are 

 termed synergists and are added to 

 nicotine sprays in small amounts. 

 The following compounds increased 

 the kill when added to nicotine 

 sprays at the rate of one part of the 

 synergist to 4,000 parts of the spray 

 material : Dibutyl hexahydrophthal- 

 ate, tributyl phosphate, and butyl 

 fumarate. 



In the course of experimental 

 work it was found that one com- 

 pound was rather highly toxic in it- 

 self when used against aphids. In 

 fact, it appears to be somewhat more 

 toxic to aphids than is nicotine used 

 at the same concentration. This 

 compound has the formidable name 



22 



