234 THE APPLE 



increase in the number of the insects and by the worm infestation 

 of a very large proportion of the fruit the following season. 



The lesson taught by this costly experience is that if we would 

 produce fruit sound and free from blemish, which will keep long 

 enough to be in good market condition when demands are greatest 

 and will be attractive enough to draw the best prices and to net 

 returns sufficient to make fruit-growing profitable, then we must 

 spray thoroughly and with judgment every year — not spasmodically 

 or carelessly as our fancy may dictate. 



What to spray for. The protection of apples against insects 

 and diseases by spraying is really a simple matter. It may be 

 divided into four common forms of treatment : 



i. The use of fungicide to prevent the germination of the 

 spores of fungous diseases, such as apple scab. Bordeaux mixture 

 and lime-sulphur are the leading fungicides. 



2. The use of an arsenical poison (a poison with arsenic as its 

 base) in controlling biting insects. The codling moth and all the 

 leaf-eating insects come under this head. Lead arsenate, arsenate 

 of lime, Paris green, etc. are the best arsenical insecticides. 



3. The use of a contact poison like kerosene emulsion, whale- 

 oil soap, or tobacco solution to destroy sucking insects. Plant 

 lice and many of the true bugs are controlled in this way. 



4. The use of a lime-sulphur wash as a winter or early spring 

 spray against scale insects such as the San Jose scale or the oyster- 

 shell bark louse. 



The first two of these forms of treatment are those most com- 

 monly employed, and may be successfully combined. 



Materials to use 



Lime-sulphur, self-boiled. Formula : 8 pounds stone lime, 

 8 pounds sulphur, and water enough to make 50 gallons. 



It is often convenient to prepare the self-boiled mixture in a 

 barrel, using quantities about three times that of the regular for- 

 mula — that is, 24 pounds of lime, 24 pounds of sulphur, and 

 about 150 gallons of water. The larger quantity of lime slaked 

 at one time results in a greater amount of heat than is obtained 

 by preparing it in three 8-pound lots, as suggested by the standard 



