New York Agricultural Experiment Station. 331 



the fine sieve, except the small amount of sand which may be in the 

 four pounds of quicklime. Mix so that the blue copper compound 

 will be prefectly evenly distributed throughout the whole mass." 



Bordeaux dust may also be prepared by making a standard 

 bordeaux mixture and allowing it to stand until the blue precipitate 

 has settled. The clear water is then poured off and the blue precipi- 

 tate thoroughly dried and ground between millstones to a fine pow- 

 der. A similar article is offered in trade under various names. 



According to the Vermont Experiment Station these dry mixtures 

 are much inferior to the standard mixture properly made and 

 promptly applied — so much so that their use is not to be recom- 

 mended. In experiments in which they were applied wet, these pow- 

 ders settled very rapidly ; and when applied dry, even in most liberal 

 amounts, they were even less effective than were the same powders 

 in wet form. 



Some have reported good results from the use of bordeaux dust 

 against the ripe rot of stone fruits while others have had opposite 

 results. The use of the bordeaux dust on ripening fruits is still 

 in the experimental stage. It is not yet to be definitely recom- 

 mended. 



Copper Sulphate Solution. 



Copper sulphate i pound. 



Water 15-25 gallons. 



This solution is sometimes used as a winter spray. It must be ap- 

 plied only before the buds start, as it is injurious to foliage. The 

 objections to it are that it is not easily seen on the tree and it is easily 

 washed off by rains. On the whole, bordeaux mixture is generally 

 to be preferred. 



A much weaker solution, consisting of i pound of copper sulphate 

 to 200-300 gallons of water, is sometimes recommended as a substi- 

 tute for ammoniacal copper carbonate in spraying ripening fruit, 

 especially peaches and plums. It appears that this solution cannot 



