18 



DECIDUOUS FRUIT INSECTS AND INSECTICIDES. 



FIRST BROOD OF MOTHS, OR SUMMER MOTHS. 



Time of emergence (fig. 7 and Table XV). — The records of emergence 

 of the first brood of moths are from band-record material and should 

 closely represent the actual time and rate of appearance of moths 

 in the field. The larvae used in these experiments were from three 

 separate band records (see Table XV), and the curve of figure 7 

 represents the sum total of daily emergence from the combined 

 sources. The first moth appeared July 26; a maximum of emergence 

 occurred August 22, after which date only a few moths issued; the 

 last moth of the brood emerged September 8. 



From the point of view of mechanical control the time of emergence 

 of moths of the second brood of the codling moth becomes of foremost 



Fig. 7.— Emergence curve of summer brood of moths in 1910, at Douglas, Mich. (Original.) 



importance, and this is one of the phases in the life history of the 

 insect in which the literature on the codling moth is particularly 

 deficient. This is mainly because of the difficult task of establishing 

 accurate data, which at present involves carefully conducted band-, 

 record experiments. It is necessary that the bands be started in 

 proper time and that the larvae be collected at regular and preferably 

 at short intervals (three days) in order that the records on the 

 emergence of moths may become fully reliable. 



Time of oviposition. — The so-called stock-jar experiments of Table 

 XVI, including moths of the first brood, have been carried out under 

 identically similar conditions as described on page 13 for the spring 

 brood of moths. Egg deposition commenced from two to three 

 days after the time of emergence of the moths, and extended on an 

 average over a period of one week. In one instance eggs were laid 

 18 days after the date of emergence of the moths. 



