6 EXPERIMENTS ON THE APPLE WITH SOME NEW FUNGICIDES. 



represents the time of the second treatment for that disease, the first 

 one being made just before the petals open. 



The second appHcation, on June 11, while it answered very well 

 under the conditions at Winchester, miglit be regarded as a little 

 late. June 1 to 5 would be a better time for this application in ordi- 

 nary years. This application is intended to catch the codling moth 

 at the time of hatching and feeding, and as the trees are just in full 

 leaf it is the best single treatment for apple leaf-blight or leaf-spot, 

 though a little late for the cedar-rust fungus. 



The third application was made on July 19. This was also perhaps 

 a week too late, but is an excellent date for the last summer treatment 

 for fruit spots and leaf diseases and is timely for the second brood of 

 codling moths and for the lesser apple worm. The spray applied at 

 this time is expected to cling to the fruit and foliage and protect them 

 from fungous attacks for the rest of the season. Only under un- 

 favorable conditions and on varieties subject to attack by the bitter- 

 rot fungus are later treatments necessary. In unfavorable seasons 

 one or, perhaps, two additional treatments might be necessary for the 

 bitter-rot. 



The dates specified were arranged in conference with Prof. A. L. 

 Quaintance, of the Bureau of Entomology, who is responsible for such 

 matters as relate to insects and insecticides in this circular. 



PREPARATION OF THE SPRAYS. 



Plat 2, standard Bordeaux mixture, 3-3-50 formula. — Heretofore, 

 stronger mixtures of bluestone and lime have been regarded as the 

 standard, but for the purpose of this experiment the 3-3-50 Bordeaux 

 mixture was used as the standard. It was made up in the ordinary 

 way, a stock solution of bluestone and a stock mixture of slaked- lime 

 paste being used. The materials were diluted and run together by 

 gravity into a tank. 



To this mixture, as to all the other fungicides, 2 pounds of arsenate 

 of lead mixed up to a cream and passed through a sieve were added as 

 the last step before filling into the spray tank. The result was a 

 rather light sky-blue mixture, which stood up very well without 

 settling. 



Plat 3, iron Bordeaux mixture. — On plat 3 was used standard 3-3-50 

 Bordeaux mixture, as on plat 2, to which 3 pounds of dissolved iron 

 sulphate diluted in about 6 gallons of water were added. Space was 

 left in pouring the bluestone and lime together to allow for the addi- 

 tion of the diluted iron sulphate. The iron produced a brown color.'^ 



o The addition of iron sulphate to Bordeaux mixture as a sticker has been recom- 

 mended by Prof. A. D. Selby, of Ohio. 

 [Cir. 58] 



