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on a commercial scale, stored and doled out as needed by the 

 grower. Hence I regard the nonadaptibility of bordeaux to 

 commercial manufacture as one of two chief causes for its 

 final abandonment for general use against apple scab, 

 though I, of course, believe the question of injury to fruit 

 and foliage the more immediately potent cause. The climax 

 was reached about 1909-10 when lime-sulfur appeared on the 

 spraying horizon of our western apple sections. Its con- 

 quest of the east, the stronghold of bordeaux and conserva- 

 tism, has been most complete. It is uncommon to find in the 

 State of New York an apple grower who still clings to bor- 

 c'eaux. Lime-sulfur, commercial lime-sulfur, if you please 

 is the fungicide of the day. That it has come to stay I 

 doubt, that it will never be replaced by bordeaux I am quite 

 sure. Copper as the active principle of fungicides has had 

 its day. Sulfur formerly the basis of all fungicides is again 

 coming into its own and that with a vengence. 



Philosophy of Spraying. Let us consider carefully the 

 why of our employment of spraying for the control of the 

 apple scab. It is required of a fungicide (1) that it shall 

 be effective against the fungus to be combatted, i.e. it shall 

 prevent the germination and growth of the fungus spore. 

 Both lime-sulfur and bordeaux conform to this requirement. 

 (2) It shall not at the strength effective against the fungu* 

 cause injury to the host plant. Here the bordeaux most 

 frequently fails and that too under weather conditions most 

 favorable to the fungus. To be sure lime-sulfur may cause 

 mjury but it is far less common and serious than in the 

 case of bordeaux.. Most of the injury reported due to the 

 lime-sulfur, results from applying it to badly scabbed or in- 

 sect injured foliage. (3) It must be of a nature to go to- 

 gether with an effective insecticide especially in the case of 

 apple spraying because here the control of codling moth and 

 other insect pests is quite as important as the control of the 

 scab. Bordeaux was particularly satisfactory in this re- 

 spect, any of the standard arsenical insecticides working 

 -vvith it quite satisfactorily. The lime-sulfur on the other 



