10 Nov., 1917.] Notes on Doicnt/ Mildew. 699 



added to the mixture after neutralization lias been obtained, as shown by 

 the test paper. 



The above recipe may also be used for making copper soda mixture. 

 All that is necessary is to substitute 3 lbs. of carbonate of soda (common 

 washing soda, not baking soda) for the 2 lbs. of lime. 



Copper-Containing Powders. 



These were first proposed as subslitutos fur spraying — their chief 

 advantage is facility of application, which is as great as in the case of 

 ordinary sulphur. It was soon found that they do not adhere so well 

 as sprays, and that, therefore, the protection they afford is insufficient. 

 Nevertheless, they are a valuable supplement to spray?, especially in a 

 wet season, when repeated treatment is necessary. 



These powders are often mixed with sulphur, so that the same treat- 

 ment may combat Mildew and Oidium. Several foniiula3 are put up 

 under different proprietary names. Those suggested by Messrs. 

 Skawinski may be taken as types. The following two are mentioned by 

 R. Brunet in his recent work Maladies et Insectes de la Vigne: — 



Skawinski's powders. 

 With sulphur. Without sulphur. 



Sulphur 



Copper sulphate 



Lime 



Coal dust 



Alluvial soil, burnt and ground 



100 100 



Concerning the use of these powders the Commission previously 

 referred to reports : — 



" The effects of cupric powders have been very variable. The Com- 

 mission is of opinion that, though these powders can in ordinary seasons 

 give very good results for the defence of bunches and leaves, in a grave 

 invasion like that of 1915 they must only be looked upon as supple- 

 mentary treatments. 



Their efficacy is greatest when the vines are enveloped in fog. 



They must be used in abundance, treating each vine twice consecu- 

 tively on each side and giving, each time, a puff with the bellows, inside 

 the vine, so as to reach the branches." 



* * * ^< # :{: 



From the above it will be seen that the fungus which has recently 

 appeared in our vineyards is of a most dangerous nature — given suitable 

 climatic conditions, of course. In normal summers we have probably 

 as little to fear as California or the Cape, but last season was far from 

 normal, and, so far, the present one is proving even wetter. 



Forewarned is foreanned: to ignore the menace might mean courting 

 disaster. 



Though visitations such as would necessitate the almost weekly 

 sprayings sometimes needed in France are not to be feared here, the 



