29 
than corn. Whether the other corn-like crops, such as sorghum and 
broom corn, are liable to its attacks, I am not at present able to 
say. If the larve were capable of living upon other generally culti- 
vated cereals, the fact could not have failed to manifest itself long 
ago in badly infested regions. Much evidence of the efficacy of 
rotation has been given already, and only two or three instances 
need now be added. In a field planted to corn by Dr. Boardman, 
near Elmira, in Stark county, a part of the ground had been in 
corn for several years previously, while a part had been in rye the 
previous year. Of the first field some was heavily manured, the 
remainder not. These fields were not separated even by a fence, 
and yet when I visited them in August, it was easy to distinguish 
even at a considerable distance that part which had been in corn 
the year before from that which had been in small grain. Although 
the former in June was even more thrifty than the latter, in August 
its inferiority was evident to the most casual observer. The crop 
raised upon old corn ground, and not manured, yielded but fifteen 
bushels per acre, while that which was manured averaged about 
fifty bushels, and on the other hand that planted upon ground 
sowed to rye, and not manured at all, yielded seventy bushels per 
acre. All these fields were planted the same day, and treated pre- 
cisely alike throughout the season. A similar condition of affairs 
was found upon the farm of Col. Jackson, in this same region, 
where three fields lying side by side, showed precisely similar differ- 
ences, evidently dependent entirely upon the previous history of the 
land with respect to the kind of crop to which it had been devoted. 
In DeKalb county, evidence of the protection afforded by the rota- 
tion of crops, is afforded on a much larger scale. On a farm of 
4,C00 acres owned by Hon. Lewis Steward, near Plano, rotation of 
crops has been the regular rule; 1,60) acres of this land was 
planted to corn this year, and 700 acres were carefully examined by 
Mr. Webster. In August, only ten acres of this entire tract was 
found affected by the corn root-worm, and this was where, in the 
re-arrangement of the fields, a small tract of ground happened to 
have been planted to corn the previous year. All about Mr. 
Steward’s place, on farms where rotation was not systematically 
practiced, the damage done was serious and general. With respect 
to other measures, the history of the insect gives us little hope of 
effective treatment. During its early stages as egg, larva and 
pupa, it is scattered and hidden in the ground beyond the reach of 
any agency except local applications to the soil, and to apply these 
throughout the field would be of course impracticable except on a 
very small seale, unless some fertilizer shall perchance be found, 
which while improving the land shall likewise injure or destroy the 
insect. Hixperiments with reference to this matter can easily be 
made at small expense, and will doubtless repay the trouble, but 
will probably teach us nothing but the hopelessness of attacking the 
pest in this way. The experience of farmers commonly shows the 
advantage of enriching the ground, as a palliative merely, by 
enabling the corn to react against the partial loss of its roots, but 
this does not at all diminish the number of worms, nor protect the 
field indeed against serious loss. Since the beetle feeds at first freely 
in the field, exposed upon the corn and weeds, it would of course 
