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satisfactory method, is to use insecticides as preventives in 

 the same way that we are obliged to employ fungicides. 

 This can be accomplished satisfactorily only when one knows 

 the insects likely to cause loss and the manner in which 

 the damage is inflicted. 



It will be seen from the above that the hand-to-mouth 

 method of rushing around after insecticides and spray ap- 

 paratus after most of the foliage has been devoured, is far 

 from true economy. Systematic spraying for a definite pur- 

 pose is the keynote to success in controlling insect pests. 

 By all means know the enemy and carry the conflict into 

 the invaders' territory. This is possible only when a man 

 is moderately well acquainted with the insect pests likely 

 to cause trouble in his orchard, for such knowledge is es- 

 sential to the proper planning of a campaign. We now 

 propose to spend a little time in discussing a system of 

 spraying for the apple orchard, because such procedure can 

 be readily adapted to the control of insects in other situa- 

 tions. 



The first spraying advisable in this locality is the ap- 

 plication of a lime-sulfur wash in early spring before the 

 buds have started to any great extent. This treatment is 

 primarily for the control of San Jose scale. It has been 

 found equally effective in cheeking the blister mite, is of 

 great service in preventing outbreaks by pear psylla, and 

 is at least of limited value in destroying both oyster and 

 scurfy scale. Furthermore, this preparation possesses valu- 

 able fungicidal properties, being exceedingly serviceable 

 in controlling apple scab and is regarded as a specific for 

 peach leaf curl. 



What lime-sulfur wash shall we use? This question 

 naturally arises in connection with the above recommenda- 

 tion, particularly as there has been much activity in the de- 

 velopment of this combined insecticide and fungicide dur- 

 ing the last few years. The home-made lime-sulfur wash is 

 still one of the most successful materials which can be used 

 for controlling San Jose scale. It may be prepared in a 

 variety of ways and considerable diversity in proportions 

 is permissible without materially impairing its usefulness. 



The last two years have seen a marvellous development 

 in the East in the production of commercial lime-sulfur 

 washes, preparations which depend entirely for their efficacy 

 upon the lime sulfides in solution. Several of these washes 



