104 Journal of A f/ric^dture, Victoria. [10 Feb., 1919. 



COPPER FUNGICIDES FOR VINE DISEASES. 



By F. de Castella, Government Viticulturist. 



(Continued from page 737, Vol. XVI.) 



Copper 5oda or Burgundy Mixture. 



After Bordeaux mixture, copper soda is the most popular and widely 

 used of copper fungicides. With Victorian orchardists and potato- 

 growers it is held in high esteem, no douht owing to the considerable 

 freedom from nozzle troubles which its use insures. As has been shown 

 above ,however, in other respects, Bordeaux presents several advantages 

 over it'" which outweigh this freedom, and if it be carefully prepared and 

 properly strained the tendency to clog is so small as to be of little prac- 

 tical importance. So far as actual protection of the vine from fungus 

 diseases, there seems to be less diiference than might be expected; both 

 are excellent fungicides, as has been proved by long experience in the 

 vineyards, and more recently by the carefully conducted experiments 

 of Professor Ravaz at the Montpellier School, France. 



Victorian orchardists usually favour the 6-8-50 formula. In other 

 words, 6 lbs. copper sulphate, 8 lbs. washing soda, and 50 gallons water. 

 For viticultural purposes, this formula is too weak to provide the requi- 

 site degree of protection. As has been shown in connexion with Bor- 

 deaux mixture, anything less than 2 per cent, of copper sulphate is in- 

 sufficient to combat vine fungi with certainty. It will be noted that 

 copper soda, according to the 6-8-50 formula, only contains 1.2 per cent, 

 of copper sulphate. 



Our potato-growers employ a stronger formula, viz., 2-2^-10, which 

 constitutes a 2 per cent, mixture, and one which is, therefore, of the 

 strength usually regarded as necessary for the spraying of vines.} This 

 proportion of soda, however, is in excess of what is now deemed desirable 

 by leading French authorities, as will be seen below. 



Evolution of Copper Soda. 



Copper soda, or, as it is called in France, Bouillie hourguignonne (liter- 

 ally Burgundy pap), was first proposed by Professor G. Masson, of the 

 Beaune (Burgiuidy) Viticultural School. The method of preparation 

 he then recommended, but which has since been abandoned as alto- 

 gether faulty in the light of more recent knowledge, was as follows: — 

 " Dissolve in a boiler the required quantity of copper sulphate (2 kilos) 

 in 5 or 6 litres of water, and, while the sulphate solution is still hot, 

 add the soda crystals (3 kilos) in small quantities at a time, stirring 

 briskly the while with a wooden stick. When the crystals are com- 

 pletely dissolved, dilute the mixture with water to 10 litres."J 



Modifications were soon introduced. Already, in 1893, Viala, in 

 Maladies de la Vigne, writes concerning copper soda as follows :— 



"Bouillie hourgxiignonne and Bouillie herrichwine. — M. Masson and 

 M. Patrigeon have proposed the substitution of commercial carbonates of 



* Its main advantages are greater adhorence, less tendonry to Ijiirn the foliage, less depressins 

 action on vegetation generally, and slower deterioration after mixing, especially in hot weather. 

 Another advantage of Bcirdeanx is its suitability for the addition of casein to increase spreading power ; 

 this substance can only be added to an alkaline mixture, and, as will be shown below, alkaline copper 

 Soda is not to be recommended. 



t See McAlpine, Journal of Agriculture, Victoria, February, 1911, p. 126, and Ramsay, Journ'd of 

 Agriculture, Victoria, August, 1014, p. 499 



t M. Masson, !■ Progr^g et Vitiale, 1887, p. 513. 



