60 



number of broods in Idaho these, I believe, would be sufficient. In 

 short, the poison is put in the calyx cup, the calyx closes, and when 

 the young larva enters the calyx for its first few meals it gets some of 

 the poison. As about 60 per cent enter the apple at this point, it is 

 very plain that this is the golden opportunity in this combat. Pro- 

 fessor Aldrich finds that 41 per cent of the larvae entering the calyx 

 end are destroyed by this spraying. An insect killed at this time not 

 only saves the apple, but reduces the number of the insects of the fol- 

 lowing broods. By a single spraying and by banding one prominent 

 grower tells me that he can save 50 per cent of his apples. Many peo- 

 ple spray only once a season, and consequently the effect of it is lost 

 later in the season. If rains wash off these sprays, they should be 

 repeated immediately. 



The next spraying should be done when the second brood is enter- 

 ing the fruit. Find the maximum of the preceding brood going under 

 the bands and spra}^ about two weeks later. It would probably be 

 better to spray a few days earlier than two weeks. A few growers 

 watch the increase of spots on the apples. The later sprayings should 

 be determined in the same way. Other sprayings can be done with 

 profit on account of the overlapping of the broods, but they should 

 be made as near the maximum of egg-hatching as possible. In fact, 

 late in the season, when the maximum is poorly defined, a spray is 

 more or less effective at any time. Last year (1900) the dates, accord- 

 ing to band records, for most effective spraying were June 10-15, July 

 27, and September 5. No inflexible rule can be given for these dates, 

 as each grower has different conditions to meet and seasons vary. 

 Each grower must determine these dates for himself. The greater 

 number of the growers simply space off the season and spray at 

 empirical times, without regard to the stage of the insect, and obtain, as 

 a consequence, poor results. 



It has been clearly demonstrated that these few sprayings alone are 

 not always sufficient to control the insect. If the sprayings were made 

 every week, the insect could be controlled, but this is too expensive. 

 The spray is effective only for a short time, and must be supplemented 

 by something to take the insects which enter the fruit between the 

 sprayings. Banding has been found to be the most efficient in this 

 connection. 



Many people object to the use of arsenites for later sprayings on 

 account of the liability of poisoning those Avho eat the fruit. 1 

 believe this objection is not well taken, since one would have to eat an 

 enormous quantity of apples to be affected. If a large amount of 

 poison remained in the hollow around the stem of an apple, there 

 might be some danger. I have eaten many apples upon which the 

 spray still remained and experienced no evil effects. 



During the growing period of the larvae the infested apple may be 



