Spraying as an Educator 321 



ment of varieties. Those persons who grow in a large 

 way for the general and more or less staple markets find 

 themselves inquiring for those varieties that are least 

 susceptible to disease- and insect-injury and which, there- 

 fore, need the smallest attention in the way of protection. 

 On the other hand, the protection that spraying affords 

 tends to bring back many of those good old varieties that 

 have almost disappeared from cultivation because of dis- 

 ease. Those persons who are growing special kinds of 

 fruit for particular or personal markets, or for home use, 

 will choose the varieties of ideal qualities in spite of the 

 liability to insect or fungous attacks. 



3. Spraying demands closer study of the companion- 

 ships and inter-relations of crops, fungi and insects. Cer- 

 tain pests follow the round of certain crops, and when the 

 planter breaks such a rotation he also lessens the liability 

 of attack. It also forces the use of shorter rotations, for 

 it is a very nimble insect or fungus that can keep pace 

 with a lively and resourceful farmer. He learns that the 

 best treatment of the red-rust on raspberries is a short 

 rotation rather than spraying. The best treatment with 

 many diseases may be a combination of both; but he will 

 find that if he reduces the number of crops to two or at 

 most to three, and then has plantations coming on in 

 other places, he will suffer comparatively little. The same 

 suggestion is applicable to the cultivation of strawberries, 

 and other short-generation fruits. 



4. Spraying emphasizes the importance of better care, 

 that the crop may repay the cost of the extra treatment. 

 The potato bug has no doubt exercised a very pronounced 

 influence in improving the cultivation of the potato, and it 

 is already apparent that the San Jose* scale is increasing 

 the alertness in fruit-growing. 



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