20 



usual crop, this field having been in broom corn for 12 or 13 years. 

 The condition of the roots was precisely that produced by the corn 

 root worm, although at that late date none of the larvae were to be 

 found in the ground. No facts have as yet come to my knowledge 

 which indicate that diversities of season have any appreciable in- 

 fluence upon the numbers or activity of this insect, though during 

 seasons favorable to the growth of the corn, less damage is, of 

 course, perceptible. 



I feel bound to do my best to excite the serious apprehension 

 of farmers respecting the future of the corn root w-orm in regions 

 where it is being neglected. I have no doubt that under such cir- 

 cumstances, multiplying continuously as it is liable to do, it will in 

 time accumulate in such numbers as no longer to confine its chief 

 injuries to fields principally in corn, but that the beetles will be 

 early forced to scatter, in search of food, from the fields in which 

 they emerged, and that the eggs will consequently be freely laid 

 everywhere in the ground instead of being confined, as now, chiefly 

 to corn fields. Indeed, there is already some serious indication of 

 the approach of this calamity. From Mr. B. C. Davis, of French 

 Grove, in Peoria county, I learned this fall that the adult beetle 

 has been seen in his vicinity, flying in swarms, so early in the 

 season that it is not at all likely that the females had yet deposited 

 the principal part of their eggs. In such cases the ground will 

 almost certainly be heavily stocked with the eggs wherever a 

 sufficient food supply occurs, and fields not lately in corn will be 

 liable to show next year evidences of serious injury by this pest. 

 As the beetle lives largely upon the pollen of plants, and con- 

 gregates upon clover heads and other late blooming flowers, it is 

 in fields of clover, or those containing an unusual amount of fresh 

 young vegetation, that this prevalence of the corn root worm is likely 

 to be noticed. 



It is not unlikely that the abundance of grasshoppers in corn 

 fields in some parts of the State this autumn, and the consequent 

 diminution of the ordinary food supply of the corn root worm beetle, 

 may have forced it to leave the corn fields earlier than is its cus- 

 tom. But this consideration serves to enforce the importance of 

 a general and frequent rotation of crops as a safeguard against 

 a pest so liable to take advantage of even slightly favoring circum- 

 stances, and to inflict uncontrollable damage upon the principal 

 farm crop of the State. 



As a very effective precaution against a possible injury to corn 

 by the root worm on ground not last in corn, I would suggest the 

 early fall plowing of such fields. By thus destroying the food of 

 the adult before the season for the laying of the eggs, all tempta- 

 tion to resort to these fields will be removed. To this end, ground 

 in clover, or that covered with any sort of late blooming vegetation, 

 or with a fresh growth of tender herbage, like volunteer oats, should 

 be plowed before the middle of October, if intended for corn. 



The ravages of this insect are, so far, curiously limited to north- 

 ern and central Illinois. Near E.lgewood, in Effingham county, I 

 failed to find any evidence whatever, either in corn fields or upon 

 thistle blossoms, of the presence of this insect as late as Septem- 

 ber 12, at which time the beetle was superabundant as far south as 



