46 REPORT OF THE STATE ENTOMOLOGIST I92I 



The wheat heads prior to examination were classed as short, 

 medium and long and an examination of the above data shows an 

 estimated loss in the crop of 26 per cent in the short heads, 1 1 per 

 cent in the medium heads and 9 per cent in the long heads. These 

 figures are obtained by doubling the number of spikelets to get the 

 maximum number of kernels or grain and making no allowance 

 for reduction by other causes. The estimated reduction for short 

 heads was 1570 and the poor kernels numbered 851. For medium 

 heads the estimated reduction was 1369 and the number of poor 

 kernels was 131 1. For the long heads, the estimated reduction was 

 762 and the poor kernels amounted to 940. It will be noted that 

 the estimated reduction for the short heads is just about twice the 

 number of poor kernels, that the figures coincide almost exactly in 

 the medium heads, while in the long heads, there is a perceptible 

 excess of poor kernels. 



This condition is probably explainable by the relative vigor of 

 the plants. Those producing short heads suffered more severely 

 from the attack and a larger proportion blasted before they could 

 develop to any extent. In other words, a considerable part of the 

 crop from the short heads was an almost total loss. The medium 

 heads possessed a fair degree of vitality and as a consequence, the 

 poor kernels almost exactly equalled the estimated loss in the crop. 

 The long heads were on the most vigorous plants producing two 

 and occasionally three grains to the spikelet, consequently the esti- 

 mated number of poor kernels of wheat is exceeded by the actual 

 number. The last group, in other words, produced a large crop as 

 a result of unusual vigor and in spite of midge injury, although 

 the actual reduction due to injury by the maggot may have been as 

 great or nearly as great as in the case of plants producing short or 

 medium heads. 



The following summary gives a somewhat clearer ider> of the 

 distribution and the abundance of the wheat midge in various sec- 

 tions of the State: 



Summary of estimated yield, yield and approximate losses, 19 19 



Estimated 



yield Yield Per cent 



County kernels kernels Reduction 



Cattaraugus 124 no n 



Cayuga 912 874 10 



Erie 366 331 9 



Genesee 5 208 4 294 17 



Livingston 3 332 2 849 14 



Monroe 2514 I 979 21 



Niagara 1 376 996 27 



Onondaga 1 170 1 126 3 



Ontario 802 734 8 



Orleans 1 328 1 084 3 



Oswego 1 192 I 124 5 



