BULLETIN 911, U. S. DEPARTMENT OF AGRICULTURE. 



Table IX. — Time of emergence and sex of moths of the spring brood of the grape-berry 

 moth, Sandusky, Ohio, 1917. 



Date of emergence. 



June 9. . 

 June 10. 

 June 12. 

 June 13. 

 June 15. 

 June 18. 

 June 17. 

 June 18- 

 June 19. 

 June 20. 

 June 21. 

 June 22. 

 June 23. 

 June 24. 

 June 25. 

 June 26. 

 June 27. 

 June 28. 

 June 29. 

 June 30. 

 July 1. . 

 July 2. . 

 July 3. . 

 July 4. . 

 July 5. . . 

 July 6.. 

 July 7. . . 

 July 8. . . 

 July 9. . . 



Number of moths. 



? i $ Tota 



1 

 3 

 3 

 1 

 2 



3 



17 

 28 

 2 

 19 

 81 

 9 

 64 



1H2 

 76 

 38 



124 

 53 

 98 

 54 

 49 

 33 

 33 

 38 

 41 

 51 

 34 

 46 



Mean 

 daily 

 tem- 

 pera- 

 ture. 



Pate of emergence. 



July 10. . 

 July 11. . 

 July 12. . 

 July 13. . 

 July 14. . 

 July 15. . 

 July 16. . 

 July 17. . 

 July 18. . 

 July 19. . 

 July 20. . 

 July 21.. 

 July 22. . 

 July 23. . 

 July 24. . 

 July 25. . 

 July 26. . 

 July 27. 

 July 28. . 

 July 29. 

 July 30. 

 July 31. 

 Aug. 1.. 

 Aug. 2.. 

 Aug. 5. . 

 Aug. 10. 



Number of moths. 



S $ i § Total 



Total. 



305 



1,116 



Mean 

 daily 

 tem- 

 pera- 

 ture. 



1 § Denotes specimens the sex of which was undetermined. 

 SPRING BROOD. 



EMERGENCE OF SPRING-BROOD MOTHS. 



In addition to the time of emergence and number of moths emerg- 

 ing each day, the sex of the moths was determined and recorded. 



Moths began to emerge June 9, but did not emerge in any con- 

 siderable numbers untilJune 22. (Fig. 2.) From this date emergence 

 was heavy for about 10 days and then fell off gradually until the 

 end of the emergence period on August 10. 



RELATION OF EMERGENCE OF SPRING MOTHS TO GRAPE BLOOM. 



The relation between the time of emergence and the blossoming 

 period of grapes is of interest in substantiating earlier records. 



Table X. — Relation between the time of emergence of the spring brood of grape-berry moths 

 and the period of grape bloom, Sandusky, Ohio, 1917. 



Period. 



Dates inclusive. 



Male moths. 



Female 

 moths. 



Sex undeter- 

 mined moths. 



Total. 



Num- 

 ber. 



Per 

 cent. 



Num- 

 ber. 



Per 

 cent. 



Num- 

 ber. 



Per 

 cent. 



Num- 

 ber. 



Per 

 cent. 



Before grape bloom 



During grape bloom 



Ten days after bloom 



Remainder of season 



June 9-20 



21 

 179 



52 

 53 



6.88 

 58. 68 

 17.05 

 17.38 



36 

 522 

 313 

 245 



3.22 

 46.77 

 28. 04 

 21.97 



5 

 17. 



8 

 13 



11.63 



39.53 

 18.60 

 30.24 



62 

 71S 

 373 

 311 



4.23 



June 21-July 1 . 

 July 2-11 



49.04 

 25.47 



July 12-Aug. 10... 



21.25 



Total 



305 





1,116 





43 





1,464 











