206 BULLETIN NO. 62. 



that has been obtained at present is 29c a pound in Minneapolis 

 This gas can be obtained in the Atlantic states for about 4c a pound 

 and it is probable that better figures can be obtained for Montana. 

 A recent letter from H. L. Frost & Company, Foresters and Ento- 

 mologists, of Boston, Mass., states that a force of men in their em- 

 ploy, using this gas, in spraying lime and sulphur wash put out 700 

 gallons with $1.60 worth of gas. 



Two lines of hose are all that can usually be used to good ad- 

 vantage even on power outfits. In spraying orchards it is often de- 

 sirable to have an elevated platform attached to the wagon in order 

 that the operators of the poles may be elevated to where they can 

 spray thoroughly in th tops of the trees as well as among the lower 

 branches. 



A device is made by the Spraymotor Company of London, On- 

 tario, and Buffalo, New York, by which the fluid coming from the 

 tank before entering the two lines of hose is cleaned of any objects 

 that would clog the nozzles. By its use much time may be saved 

 particularly where it is necessary to use water from an irrigating 

 ditch which has many small floating bodies in it. 



WHEN TO SPRAY. 



A review of the facts of the life history of the codling moth 

 indicates clearly that in timing the different sprays that are applied 

 we should in the first place spray so as to lodge the poison in the 

 calyx cup before it closes. Though the larvae of the first generation 

 m.a}- not hatch until some time after the cups have closed, they 

 nevertheless to a large extent, go in at the blossom end of the fruit. 

 Ii is highly desirable, therefore, that the poison be in these cups 

 when the larvae arrive. It is fortunate that the poison lodged in 

 the caylx while open is retained there and more or less protected by 

 the closing of the calyx lobes against being washed out by rain. 



Since a part of the larvae of the first generation and a much 

 larger proportion of the second enter the fruit from the side, it is es- 

 sential that the general surface of the fruit be also covered with 

 poison, and since the larvae may be found going into the fruit in 

 most abundance at about June 15 for the first generation and about 

 August 12 to 15th for the second, these dates should be considered 

 as critical times. It would be well therefore to have the dates of 



