PREVENTIVES OF FUNGOUS DISEASES 269 



Combining Insecticides and Fungicides 



In many cases it has been found that a fungicide is also 

 of value as an insecticide, and vice versa. In others, it is 

 easy to add an insecticide to the fungicide solution, and thus 

 prevent both classes of injury by one application. A Bor- 

 deaux mixture with arsenate of lead added is the combina- 

 tion most frequently used in the past, but it seems likely to 

 be displaced by the combination arsenate of lead and the 

 lime-sulphur wash. 



" The successful orchardist of the future," writes W. M. 

 Scott, " will be the man who, among other things, studies 

 the conditions existing on his own farm and sprays his 

 trees according to the needs of each variety for the control 

 of the particular troubles which occur in his locality. 

 The course of treatment best suited for the orchards 

 of the Shenandoah Valley of Virginia may not neces- 

 sarily give the best results, in orchards situated east of 

 the Blue Ridge in that state, and again the treatment for 

 certain varieties of apples may be different from that re- 

 quired for certain other varieties growing in the same 

 locality. The course of treatment should be planned not 

 only with reference to the diseases to be controlled, but 

 also with reference to the probable effect of the fungicide 

 upon the fruit and foliage of the variety to be treated. 

 The Ben Davis, for example, is so seriously russeted by 

 applications of Bordeaux mixture that often most of the 

 fruit sprayed with this fungicide is rendered second class. 

 In Virginia this variety does not suffer materially from the 

 attacks of scab, bitter rot, or other serious fruit diseases, the 

 leaf spot which is easily controlled being its chief fungous 

 enemy. The Ben Davis in Virginia and in other similar 

 situations may therefore be successfully sprayed with a 



