Treatments for Downy Mildew. 93 



entitled : " Treatment of the Downy Grape Mildew (JPerono- 

 spora viticola) and the Black Rot (Phoma uvicola)." The five 

 remedies mentioned in this circular were all copied from the 

 French journals. The directions were in brief as follows : 



" For Peronospora. 



1. " Dissolve in 10 gallons of water 5 pounds of the sulphate 

 of copper." This was to be used for soaking the stakes and all 

 tying material, and was also to be sprayed upon the foliage, 

 using for the purpose any fine spraying apparatus, the cyclone 

 nozzle being suggested as the best for the purpose. 



2. "Make a mixture of lime and water, as one ordinarily 

 applies whitewash." Apply as above, but repeat after rains. 



3. This was the formula for the " copper mixture of Gironde," 

 as given on a preceding page. 



4. " The powder of Podechard." This contained 225 pounds 

 of air-slaked lime, 45 pounds of sulphate of copper, 20 pounds of 

 flowers of sulphur, 30 pounds unleached ashes, and 15 gallons of 

 water. 



5. " The ordinary milk-kerosene emulsion, with the addition 

 of from 2 to 5 per cent of carbolic acid and the same percentage 

 of glycerine, and then dilute 1 part of the emulsion in 20 to 50 

 parts of water. Spray on the under surface of the leaves by 

 means of a cyclone nozzle of small aperture. 1 ' l 



For black rot, the mixture of lime and sulphate of copper 

 was particularly recommended, and in addition to this a free 

 use of Podechard's powder, upon the ground in the vineyard, 

 was advisable. 



Scribner wrote as follows concerning the above circular : 

 "Three thousand of these circulars were distributed, and I 

 have reason to believe that many made a trial of one or more 

 of the remedies proposed, but I regret to say that few responded 

 to the request that the results of these trials be reported to the 

 Department." 2 A report was received from George M. High, 

 Middle Bass, Ohio, the letter being dated Dec. 28, 1886, in 

 which he speaks of having poor success with formula No. 2, 



J - This formula had previously been published by Kiley in Rural New- Yorker, 

 1886, Feb. 6. 



2 Ann. Eept. U. S. Com. of Agric. 1SS6, 100. 



