PROCEEDINGS, 1918 59 



tosh Red variety, three applications of 3-10-40 Bordeaux were 

 able to check, almost completely, a very severe outbreak of 

 apple scab, giving fruit practically free from this disease, while 

 over 90% of the unsprayed apples were affected. In some 

 cases,the strength of lime sulphur recommended by the various 

 State Experimental Stations and State and Provincial Depart- 

 ments of Agriculture, have given rather better scab control than 

 2-10-40 Bordeaux. In others, the latter mixture has given su- 

 perior results. An analysis of the control to date, shows little 

 to choose between them in the single factor of fungicidal value. 

 As regards injury from their use, however, the Bordeaux thus 

 prepared, is markedly superior. 



Lastly, with regard to this compound as a carrier for ar- 

 senical poisons, laboratory feeding tests show that the killing 

 value of the mixture is slightly but definitely less than when 

 these poisons are used in ordinary Bordeaux. Since ordinary 

 Bordeaux reduces considerably the toxic value of arsenical 

 compounds,the necessity of increasing the strength of the poi- 

 son when used in Bordeaux with a high excess of lime is thus 

 indicated. As would be expected the injury from all arseni- 

 cals proved to be much less than when the same arsenicals 

 were used alone or in combination with sulphide sprays. 



While definite experiments have not been carried on by 

 the writers for the long period of years necessary to clear up 

 all points in connection with this question, they feel that the re- 

 sults herein recorded may be important in calling attention 

 to the value of Bordeaux formulae with a much higher excess 

 of lime than have ordinarily been employed in apple spraying. 

 Though final conclusions are not possible at the present time, 

 nevertheless, we believe that the following are correct for Nova 

 Scotian conditions, at least for the period that this subject 

 has been studied by us: 



1. Neutral Bordeaux mixtures, such as Woburn Bordeaux 

 are not superior as fungicides, under actual field conditions, 

 to ordinary Bordeaux made with equal parts of lime and copper 

 sulphate, and such neutral Bordeaux cause very much more in- 

 jury to apple foliage. 



2. Bordeaux mixture made up to the formula of 3-10-40 

 or 2-10-40 has a higher fungicidal value than sulphide sprays in 

 safe dilutions. 



3. Leaf yellowing and other Bordeaux leaf injury is re- 

 duced to a minimum, if not entirely eliminated, by the use of 

 such formulae. The benefits in the form of freedom from in- 



