oo ■ Maine; agricui^tural experiment station. 1913. 



injured by bordeaux mixture. Moreover the work of Stewart 

 and his associates of the New York Station has shown that 

 Hme-sulphur not only is far inferior to bordeaux mixture as an 

 agent to control the late blight and other potato leaf-diseases, 

 but it is apparently positively detrimental to the potato.* 

 Therefore it seemed justifiable to plan a series of experiments 

 extending over a number of years in which the relative efficiency 

 of bordeaux mixture and lime-sulphur as a spray for apple or- 

 chards could be tested under a variety of seasonal weather 

 conditions. While the reports are everywhere quite favorable 

 to lime-sulphur, as an orchard spray the data so far accumu- 

 lated are not sufficiently varied and complete to draw final con- 

 clusions. If bordeaux mixture is more effective or even equally 

 effective in scab control there is no reason for the orchardist 

 who experiences no injur}' from it upon the varieties which he 

 grows to discard it in favor of lime-sulphur. 



Certain writers, a summary of whose work Mr. Bonus gave 

 in Bulletin 198 have noted the fungicidal value of lead arsenate. t 

 Therefore the experiments for 1911 were so planned as to in- 

 clude a test of the fungicidal value of lead arsenate, further 

 comparisons of the fungicidal value of bordeaux mixture and 

 home-cooked lime-sulphur, and a test of different dilutions of 

 lime-sulphur to determine which is the most satisfactory 

 strength to use, both with regard to control of scab and freedom 

 from spray injur}^ The variety used for making these tests in 

 all cases being the Ben Davis. 



On account of weather conditions being unfavorable to the 

 growth of the fungus practically no scab developed in the or- 

 chards in 1911 so that from that standpoint no data of value was 

 secured. In fact on account of the failure of scab to develop 

 the only clear-cut result of the experimental spraying of that 

 year was with regards russeting the fruit. Where bordeaux 



* Stewart, F. C. and French, G. T., Lime-Sulphur vs. Bordeaux Mix- 

 ture as a Spray for Potatoes. Bui. N. Y. Agr. Exp. Sta. 347, 191 1. 

 Munn, M. T., Lime Sulphur vs. Bordeaux Mixture as a Spray for Pota- 

 toes IL Bui. N. Y. Agr. Exp. Sta. 352, 1912. 



t Taylor, E. P., Spraying Peaches for Brown Rot, Western Fruit 

 Grower, pp. 20-21, Oct. 1909, pp. 16-18, Feb. 1910. 



Wait, M. B. Experiments on the Apple with Some New and Little 

 Known Fungicides, Cir. U. S. D. A. Bu. PI. Ind. 58, 1910. 



Wallace, E., Blodgett, F. M. and Hessler, L. R. Studies of the Fungi- 

 cidal Value of Lime Sulphur. Bui. Cornell Agr. Exp. Sta. 290, 191 1. 



