NEW YORK STATE MUSEUM 39 



is of considerable practical importance, since it means, if this be 

 the case, that infestations must originate in most cases from migrat- 

 ing moths and the usual appearance of the pest in corn during 

 September and October also tends to support current opinion 

 respecting the habits of this insect. 



There is no question but what the corn ear worm winters success- 

 fully a little south of New York State. Dr T. J. Headlee, state ento- 

 mologist of New Jersey, informs the writer that the corn ear worm 

 unquestionably winters in their soils. On the other hand, Dr W. R. 

 Walton states that the winter mortality of this insect, even so far 

 south as central Virginia, is normally very heavy. Doctor Walton 

 thinks it safe to assume that the northern limit of hibernation is 

 normally somewhere in the neighborhood of 42 ° north latitude. 

 The above general statements agree very closely with known con- 

 ditions regarding the corn ear worm so far as New York State is 

 concerned. 



The eggs of moths flying in midsummer or later are frequently 

 deposited upon corn silk and the young caterpillars enter the tips 

 of the ears and feed very largely upon the developing grain, though 

 in cases of unusually severe infestation there may be damage to 

 the stalk and the tassel very similar to that caused by the European 

 corn borer. Ordinarily this latter does not occur. Partly grown 

 to full-grown caterpillars spoil ears for domestic purposes and if 

 the infestation is general, may seriously damage crops of field corn. 



Characteristics of the insect and its work. The full-grown 

 caterpillars are about iy' 2 inches long and vary greatly in color 

 from a light green through a rosy color and brown to almost black. 

 They may be either striped, spotted or perfectly plain. Ordinarily, 

 they present rather bright, strongly contrasting colors. They are 

 easily distinguished from the European corn borer by the larger 

 size, the minute black tubercles or warts on the body of the cater- 

 pillars, the frequently strongly marked coloration and the usual 

 limitation of feeding to the surface of the ear. Ordinarily, the 

 corn ear worm is not a borer. 



Control measures. With the above limitations in mind, and 

 they appear to apply strictly to this species, we are forced to the 

 conclusion that ordinarily remedial measures for the control of 

 corn ear worm are impractical in the New York corn-growing areas, 

 because serious damage is so uncommon. Furthermore the abundance 

 of the insect one season, if it is unable to withstand our severe 

 winters, and such appears to be the case, means little or nothing 



