270 JOURNAL OF ECONOMIC ENTOMOLOGY [Vol. 9 



By far the most serious and widespread white grub outbreaks on 

 record are those of 1912 and 1915, the beetles for these broods occur- 

 ring in the years 1911 and 1914, respectively. The area of these 

 infestations included southeastern South Dakota, northwestern and 

 northeastern Iowa, southeastern Minnesota, southern Wisconsin, 

 northern Illinois, the extreme northwestern corner of Indiana, south- 

 western Michigan as well as the eastern portion of that state from the 

 "thumb district" south into Ohio; also many points in the northern 

 third of Ohio, western Maryland, northwestern and northeastern 

 Pennsylvania, southeastern New York, including Long Island, and 

 Connecticut. A less serious outbreak occurred in most of the above 

 mentioned territory in 1909, but that of 1912 was very severe while 

 the 1915 infestation was even more general and severe to cultivated 

 crops, showing a gradual increase in the abundance of grubs and in 

 the area infested. Although the grubs were more abundant and showed 

 greater damage to cultivated crops in 1915, the grass crops were no- 

 ticeably less injured, owing to the excessive rains throughout the sum- 

 mer. It was not an uncommon sight to see thirty- or forty-acre fields 

 of corn totally destroyed and more often than otherwise the corn fields 

 in the infested districts were 50 per cent destroyed. The accom- 

 panying photographs (PI. 15) give a fair idea of the appearance of 

 the infested fields in Wisconsin, Illinois and Iowa, although they do 

 not impress one with the great amount of damage actually caused by 

 the grubs. The various natural enemies now seem to be making 

 headway in controlling the grubs and the crest of this destructive 

 brood has probably been reached but it will be many years before the 

 brood again becomes normal unless some unforeseen calamity over- 

 takes it. 



In 1911 the beetles were extremely abundant and stripped the tim- 

 ber of its foliage according to reports and during the latter part of 

 May and the first of June in 1914 we made a trip across the northern 

 end of Illinois, northeastern Iowa, southern Wisconsin as far north as 

 Baraboo, thence east to Milwaukee, and through parts of Michigan, 

 and everywhere, excepting in eastern Wisconsin, the timber, which 

 consisted chiefly of oak and hickory, was completely stripped of its 

 foliage. Only red oak, the maples, conifers and fruit trees were 

 left with an appreciable amount of foliage, and the accompanying 

 photographs (PI. 16) illustrate the degree of defoliation which we found 

 in the infested localities. To further illustrate — -the beetles were so 

 abundant that the dead ones accumulating beneath the lights had to be 

 swept away each morning to prevent or at least modify the terrible 

 stench which they produced. At one small town in Wisconsin the beetles 

 accumulating beneath the ten arc lights of the town were hauled away 

 each morning for a period of ten days or two weeks, by the wagon load. 



