68 



Mr. Washburn thought it difficult to accurately count the number 

 of broods in a climate like that of Oregon, with which statement Mr. 

 Simpson fully concurred. 



Mr. Alwood, referring- to the statement made by Mr. Simpson of 

 the cost of 1 cent per tree for spray, desired to know the size of the 

 trees. 



Mr. Simpson explained that the trees were 8 years old and much 

 larger than trees of this age in the East. These trees produced from 

 6 to 20 boxes of apples, with a very good average of 10, a box equal- 

 ing approximately a bushel. The soda-lime arsenite was used. 



Mr. Burgess desired to know the cost and weight of the gasoline 

 sprayer tried by Mr. Simpson. 



Mr. Simpson stated that the cost was $320. The weight had never 

 been accurately taken so far as he knew. 



Mr. Fletcher stated that he had been much interested in Mr. Simp- 

 son's observations in Montana. He considered the duration of the 

 different broods a very interesting subject and thought that the fact 

 was established that there might be a considerable variation. He 

 questioned the possibility of drawing conclusions from orchard obser- 

 vations alone. Attention was called to the commonly noted occurrence, 

 by anyone who had bred insects, that as large a proportion as half of 

 a brood might go over for a whole period, until the next time of the 

 regular occurrence of the species, and if such observations were made 

 in the orchard, wrong conclusions might be drawn. He did not con- 

 sider it desirable that entomologists should speak of a partial brood. 



Mr. Osborn stated that in determining the number of broods he 

 considered that if the average time of appearance in greatest abun- 

 dance were taken, results would be much more reliable as a basis for 

 determining the number of broods. He mentioned a case where the 

 codling moth appeared as late as the latter part of June from apples 

 stored in a cellar where it was rather cool and development was 

 retarded. 



Mr. Marlatt said that he was very much interested in Mr. Simpson's 

 confirmation of the feeding of the larvae on the leaves, and not only had 

 this been confirmed, but our knowledge of the extent of such feeding- 

 had been much increased. The work of some earlier experimenters 

 and observers had demonstrated that codling moth larvae would feed 

 on leaves, but that they did it normally and to a considerable extent 

 in nature had not previously been so fully demonstrated. He thought 

 this was a very interesting feature of Mr. Simpson's work. It indi- 

 cated that the poison catches the caterpillar very frequently on the 

 leaves, especially as it has been shown that a considerable percentage 

 of the eggs are placed on the leaves. When one comes to think of the 

 matter it is not at all surprising that the young larvae will feed on the 

 leaves. Before entering the fruit they normally work two or three 



