AMERICAN PLUM BORER. 7 



Table II. — Emergence of spring brood of moths of the plum borer at Winchester, Va., in 



1913. (See fig. 1.) 



Date cf 

 observa- 

 tion. 



Number 

 of moths 

 emerg- 

 ing. 



Date of 

 observa- 

 tion. 



Number 

 of moths 

 emerg- 

 ing. 



Apr. 25 



29 



May 3 



7 

 11 

 15 



1 

 6 

 10 

 31 

 6 

 3 



May 19 

 23 

 27 

 31 



June 4 

 8 



Total.. 



3 

 5 

 1 

 2 

 S 

 



79 



Girault, in 1905, records one adult that emerged at Washington as 

 early as April 21 and later notes that empty pupal cases were very 

 plentiful in the field by May 2. In normal seasons adults probably 

 begin appearing in the latitude of Winchester and Washington from 

 the last of April to the first of May. Rosenfeld, in 1906, observed 

 emergence in Georgia as early as March 29, or about one month 

 earlier than it occurred at Washington the preceding year. In 1913 

 maximum emergence occurred at Winchester on May 7, twelve days 

 after the first moth appeared, and adults continued to emerge in the 

 rearing cages in lessening numbers until June 4. The seasonal 

 appearance of the moths can be more easily appreciated by reference 

 to figure 1. 



35 



3o 



I 



X 



ft .- 



\ e 



2f 25 23 



/5 /& 



23 27 3/ 





Via. 1.— Diagram showing emergence of spring brood of moths of the American plum borer 

 < Etuopkera • mifuru ralis) at Winchester, Va., in 1913. (Original.) 



OVIPOSITION OF FIRST GENERATION OF MOTHS. 



A- flic mollis emerged from day to day they were transferred to 

 jars containing twigs of plum or apple wood, nil of those issuing on 

 the miiiic date being confined in one jar and a record kept of the 

 number of eggs subsequently deposited. I'>gg* were laid freely on 

 the twigs, singly or in small groups in the cracks and crevices of I lie 



