CODLIISTG MOTH IlsT CENTEAL APPALACHIAlSr REGION. 



41 



Table XXXVII. — Resume of rearing experiments on the codling moth at four points in 

 Virginia, West Virginia, and Maryland in 1913. 



Observation. 



Hagers- 



town, Md. 



Winches- 

 ter, Va. 



Charlottes- 

 ville, Va. 



French 

 Creek, 

 W.Va. 



Total. 





Num- 

 ber. 



Per 



cent. 



Nurq,- 

 ber. 



Per 

 cent. 



Num- 

 ber. 



Per 



cent. 



Num- 

 ber. 



Per 



cent. 



Num- 

 ber. 



Per 



cent. 





2, 756 



883 



227 



1,646 



100.00 



32.04 

 8.24 

 59.72 



971 



234 

 326 



346 

 65 



100.00 



24.10 



33.57 



35.63 



6.70 



542 



223 



270 



49 



100.00 



41.14 



49.82 



9.04 



143 



48 

 41 

 51 

 3 



100.00 



33.58 



28.67 



35.66 



2.09 



4,412 



1,388 



864 



2,092 



68 



100.00 



Larvae dying from handling, cannibal- 



31.46 



Moths emersing same season 



19.58 





47.38 



Parasitized larvae 



1.55 















It will be noted that the proportion of larvse dying in the rearing 

 cages, due to handling, cannibalism, disease, etc., varied from 12.90 

 per cent to 41.14 per cent. The latter figure, however, is unduly 

 high, the average loss from this source bemg 21.12 per cent in 1912 

 and 31.46 per cent in 1913. The proportion of larvse transformmg 

 the same season as that in which they were collected varied from 

 8.24 per cent at Hagerstown to 49.82 per cent at Charlottesville, 

 with an average of 19.12 per cent in 1912 and 19.58 per cent in 1913. 

 For 1912 from 42.86 per cent to 67.14 per cent of all larvse collected 

 spun up and wintered, the average for all points being 59.42 per 

 cent. The proportion of wintermg larvae in 1913 was abnormally 

 small on account of the light fruit crop of that year. Loss from 

 winter killing amounted to from 11.21 per cent to 41.38 per cent, 

 the average for all points being 26.06 per cent. Observations on 

 parasitism were made only at Winchester and French Creek, the 

 highest recorded being 6.70 per cent at Wmchester in 1913. It must 

 be remembered, however, that the foregoing facts are taken from 

 observations of insects kept in confinement, and only in a limited 

 way indicate what occurs under normal out-of-door conditions. 



Table XXXVIII gives the numbers of codling-moth larvse col- 

 lected and reared in the course of the work in the different localities. 



Table XXXVIII. — Number of codling -moth larvse collected and reared in the different 

 localities in Virginia, Maryland, and West Virginia during 1911, 1912, and 1913. 



LocaUty. 



Year. 



Number of 



larva; col- 



VxifA and 



reared. 



Locality. 



Year. 



Number of 

 liirvaj col- 

 lected and 

 roared. 



Charlottesville, Va 



1911 

 1912 

 1913 

 1911 

 19 J 2 

 1911 

 1912 



1 218 



905 



r.'12 



1.979 



1 , H(12 



910 



1,U« 



2,079 



79K 



971 



Hagerstown, Md 



1911 

 1912 

 1913 

 1911 

 1912 

 1913 

 1911 

 1912 



1 . 761 





French (!reok, W. Va 



1,706 

 2, 75(1 



(>:i:{ 



Ftohcrevlllc, Va 



Pickoas, W. Vii 



:)39 



113 





.■ii)9 



Winchester, Va hV\ 



\'.)n 



X'.iVA 



Ti)\a\ 



■17 

 •H), 406 













