22 CONTROL OF PEACH BROWN-ROT AND SCAB. 



DANGER OF INJURY TO THE FRUIT AND FOLIAGE. 



If the self-boiled lime-sulphur is properly prepared and applied, 

 there is very little danger of injuring the fruit or foliage. In all of 

 our work during the past season not the slightest injury developed on 

 any of the several thousand trees sprayed. During the season the 

 writers examined several orchards, ranging from 200 to 500 acres, that 

 had been sprayed by the owners with self-boiled lime-sulphur. No 

 serious injury had resulted from the spraying in any of these orchards. 

 Where injury occurred at all, it was only slight and was confined to a 

 few dozen trees, except in one case where there was a general scorching 

 of the foliage throughout the orchard, due, perhaps, to too much boil- 

 ing of the mixture ; but even in this case the result was only a slight 

 thinning of the foliage, which was scarcely sufficient to damage the 

 trees. In each case the mixture was so exceedingly successful as a 

 fungicide that the owner did not consider the slight injury caused by 

 it as worthy of consideration. However, of the thousands of orchards 

 that will probably be sprayed with this mixture, there will doubtless 

 occur from time to time cases of rather serious injury. Such cases 

 in the opinion of the writers will be exceptional and will not be so 

 common or so serious as is Bordeaux injury of the apple. 



It was expected that where arsenate of lead was used in these experi- 

 ments some injury might occur, but neither fruit nor foliage showed 

 any signs of injury. In the first application of poison made when the 

 dried calyces were shedding, no lime-sulphur was used, but in the 

 second, three weeks later, the lime-sulphur mixture and arsenate of 

 lead were used in combination. It seems barely possible that the 

 lime-sulphur preparation may correct the tendency of the arsenate 

 of lead to injure, although no definite evidence on this point has yet 

 been obtained. In the experiments conducted at Marshallville, Ga., 

 last year, peach foliage and fruit sprayed with the self-boiled wash and 

 arsenate of lead combined were slightly injured, but the notes on 

 this work indicate that the injury was due mostly to the lime-sulphur 

 wash, which was boiled too long in an effort to get a large amount of 

 sulphur in solution. Some arsenate-of-lead injury will doubtless 

 occur from time to time, but where the curculio is so bad, as in 

 southern peach orchards, it would seem advisable for the owners to 

 take some risk in the use of the poison to hold this insect in check. 



DANGER OF STAINING THE FRUIT. 



There is some danger of staining the fruit with the mixture if it is 

 applied within two or three weeks of the ripening period. Mr. C. A. 

 McCue, 6 of the Delaware experiment station, reported good results 



a Circular 27, Bureau of Plant Industry, U. S. Dept. of Agriculture, pp. 6-7. 



b Bulletin 85, Delaware Agricultural Experiment Station. 



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