NEW YORK EXPERIMENT STATION BULLETINS. 375 



3. Hydrate of Copper. 



a. When the hydrate of copper is applied alone it is not so effective 

 against fungi as when applied in the Bordeaux mixture. 



b. Two applications of the hydrate reduced injury from fungi at least 

 5 per cent, when used at the rate of ^ pound in 22 gallons of water. 



c. The hydrate of copper when applied alone did little injury to the 

 foliage, only the peach being affected. 



d The caustic properties of the hydrate is increased by the addition of 

 Paris green. The peach was injured 35 per cent, by such a combination. 



4. Borate of Copper. 



a. The borate of copper, when applied in an undissolved condition, has 

 little fungicidal action. 



b. When applied at the rate of h pound in 22 gallons of water, two appli- 

 cations reduced injury from fungi about 20 per cent. 



c. The action of the borate of copper upon foliage was caustic when the 

 substance was applied in connection with Paris green, or Paris green and 

 ammonia. The foliage of the quince, apple, pear, and egg-plant suffered 

 least when no ammonia was used. When ammonia was used only the 

 egg-plant escaped injury. 



d. The borate of copper possesses no advantages over the carbonate, but 

 its action is similar to it. 



">. Chloride of Copper. 



a. The chloride of copper as a fungicide gave better results than the 

 Bordeaux mixture. When used at the rate of 3 ounces in 22 gallons of 

 water, two applications reduced injury from mildew 35 per cent. 



b. Solutions of copper chloride must be weak. One application, at the 

 rate of 1^ ounce of the chloride in 22 gallons of water, injured the foliage 

 of apple and peach trees. 



c. Paris green increases the caustic action of a solution of the chloride 

 of copper. 



6. Arsenites. 

 • / 



a. Paris green, when applied in connection with the ammoniacal carbon- 

 ate of ammonia, does more injury to foliage than would an equal amount 

 of London purple. 



b. London purple, when applied in connection with the carbonate of 

 copper held in suspension in water, does more injury to foliage than would 

 an equal amount of Paris green. 



c. London purple and Paris green increase the caustic action of the 

 ammoniacal carbonate of copper, of the carbonate of copper suspended in 

 water, of the sulphate, hydrate, borate, and chloride of copper, when 

 insecticide and fungicide were applied together. 



d. The injury done to foliage by the combinations is probably due to 

 the arsenite which is dissolved by the ammonia or the fungicide. 



7. Varieties. 



a. Some varieties of certain fruits appear to be more susceptible than 

 others to injury from the combinations. 



