THE MONTHLY BULLETIN. 23 



ANALYSES OF SOME MORE RECENT AND OLDER PEST 



REMEDIES. 



By M. R. Miller, Insecticide Laboratory. University of California, Berkeley. 



The inquiries received at the insecticide and fungicide laboratory in 

 regard to the composition of the newer insecticides and fungicides, and 

 the samples of these materials received there, indicate the interest taken 

 in them by the agricultural public. Whenever a new remedy is offered 

 for Bale it is bu1 a short time before general interest is aroused, and 

 information is soughl as to its composition and whether or not it is 

 efficienl for the purpose for which it was designed. 



The efficiency of an insecticide or fungicide depends not only upon its 

 action on the insects or fungi for which it is used, but almost equally 

 upon the action it will have upon the host. Consequently the impor- 

 tance of knowing the presence of harmful ingredients is directly equal 

 to that of knowing the presence and amounts of helpful constituents. 



Taken altogether, the new materials examined in the laboratory during 

 the past year have been found iii most cases to be more efficient than 

 inefficient remedies. Although there have been no radical discoveries 

 made by manufacturers in the way of new materials, some new combi- 

 nations of old and proven remedies are being offered. These mixtures, 

 ii 5 me cases, are of especial value to the smaller consumer as the 

 purchase and mixing of small quantities is obviated. In all cases, how- 

 ever, he should know the composition of the material he is using. 



In the tabulations given of analyses, effort has been made to eliminate 

 as many of the common materials as possible which have already been 

 analyzed, and to present only the newer remedies and those concerning 

 which there seems to be considerable doubt as to their constitution. 



BORDEAUX PASTE. 



Moisture 60.42% 



Copper (metallic) - 10.72% 



Or. as copper oxid (CuO) 13.40% 



For a fall spray it is to be used at the rate of from 8 to 10 pounds 

 to 50 gallons of water. Used at this rate the spray will contain from 

 1.07 to 1.34 pounds of copper oxid (CuO) per 50 gallons of spray 

 compared with the 1.21 pounds copper oxid contained in a homemade 

 Bordeaux mixture spray, 4-4-50 formula using bluestone which is 95 

 per cent pure. 



BORDEAUX MIXTURE, DRY POWDERED. 



Moisture 1.73% 



Copper (metallic) 11.52% 



Or, as copper oxid (CuO) 14.40% 



In order to obtain the same amount of copper oxide in a spray made 

 from this material (1.21 pounds) as there is in 50 gallons of homemade 

 spray, it will be necessary to use this dry powder at tin' rate of 8.34 

 pounds to 50 gallons of water. 



COOPER'S FUNGICIDE. 



Moisture 15.27% 



Copper (metallic) 9.85% 



Or, as copper oxid (CuO) 12.31% 



