86 JOURNAL OF ECONOMIC ENTOMOLOGY [Vol. 14 



com being 10 to 13 inches high July 7th and some early sweet com 

 mostly tasseled out by the 26th. 



Com develops so early and the moths fly so late that oviposition 

 upon the ear with little leaf or tassel injury may occur and this seems 

 to have been the case in at least one field. 



The first pupa was reported by federal men June 15th, the first moths 

 were taken in the field July 1st and the first egg masses July 8th while 

 the last moth was found in the field July 29th. There was no evidence 

 of the development of a second brood or the deposition of eggs and the 

 development to full grown caterpillars of corn borers upon plants other 

 than com, although larvae were active as late as November 12 when 

 freezing temperatures prevailed at night and snow squalls occurred in 

 the day. 



Stubble Infestation 



An area of a field having a 10.52 per cent stalk infestation was care- 

 fully examined and the 551 stalks contained 68 borers or a stalk infesta- 

 tion for this area of 12.34 per cent. The stubble was also examined, 

 each butt being cut open and only four borers were found or an infesta- 

 tion of but .72 per cent. 



Another field with an average stalk infestation of 34.85 per cent, was 

 also examined and in this case the stubble was cut rmusually high, 

 approximately 15 inches and out of 310, 42 or 13.54 per cent, were 

 infested. 



In both fields, the nirmber of borers at or below the surface of the 

 ground was very small, probably less than 0.10 per cent. 



The observ^ations in the eastern area were checked by examinations 

 in the western section and so far as could be determined, development 

 was practically identical though in the western area there appeared to 

 be a somewhat heavier infestation about Silver Creek and in certain 

 fields a relatively greater invasion of nearby plants by partly or nearly 

 full grown borers. 



The stalk infestation in the Schenectady area varied from nearly 

 35 per cent, on some river bottom fields near the presimiable center of 

 the infestation to a very sparse occurrence of the borers on the outer 

 margins of the infested territory. 



Com fields showing a stalk infestation of 10 per cent, or more were 

 limited to an irregular, narrowly triangular area centering approxi- 

 mately upon the river flats of Scotia and covering some 15 square miles, 

 the greatest extension from the presumable center being five miles up 

 the Mohawk river and about three miles back from the river. 



The area comprising fields which may show a stalk infestation of 

 from 5 to 10 per cent, covers approximately 25 square miles lying out- 



