42 NEW YORK STATE AIUSEUM 



become so numerous and widely distributed as, in a large measure, 

 to prevent the undue multiplication of this insect. Furthermore, 

 many introduced insects appear to multiply more rapidly for a few 

 years after they have become established in a new environment, 

 and this seems to have been the history'- of the wheat midge and is 

 something which many of us have watched diuing the past 2 5 years 

 in the case of the once dreaded but now scarcely feared San Jose 

 scale. 



Wheat Mfdge in Western New York 



A survey in mid- July of conditions in Erie, Genesee, Niagara 

 and Orleans counties showed the maggot to be generally present, 

 mostly in small numbers, throughout the greater part of the wheat- 

 growing area. Many of the fields had 80 to 99 per cent of the heads 

 infested and the shrunken grain varied from an average of about 

 4 per cent to as high as nearly 33 per cent, the latter being unusual. 



Wheat midge did not appear to be nearly so abundant in Ontario 

 county and other sections more removed from the four coimties 

 mentioned above. For example, very moderate infestations were 

 found in samples received from both Ontario and Oswego counties 

 and Professor Parrott has subsequently informed us that farmers 

 in the immediate vicinity of Geneva have been gratified by the 

 yields of the past two seasons, they having obtained as high as 

 42 to 47 bushels an acre. It is certain that wheat midge has not 

 greatly reduced the crop in fields producing such quantities of grain. 



The first object of this survey was to determine the prevalence of 

 the insect and the second to ascertain whether any varieties, system 

 of cultivation, time of sowing, location of field, or other factor which 

 could be readily modified, had an important influence in either 

 encouraging or preventing infestation. Many wheat fields were 

 examined throughout the area and a number of representative 

 samples taken and carefully examined in the laboratory to ascertain 

 the total number of grains, the number and percentage shrunken and 

 the number of maggots in the head. This latter varies considerably 

 and while the presence of many maggots indicates serious infestation, 

 their absence by no means proves the contrary since they frequently 

 leave the heads during rains or when there is a considerable amount 

 of moist iu"e upon the grain. 



A tabulation of these laboratory results is given below, the varieties 

 being arranged in approximately the order of their importance in 

 the region covered by the survey. 



