166 
tion of leaves of trees and shrubs in spring not infrequently cause 
the death of those preferred by them for food, and the grubs are 
particularly destructive in towns to the turf of lawns, in nurseries to 
young evergreens, in the fruit plantations to strawberry vines, and 
on the general farm to grass and corn. 
The injury by grubs is due, in all cases, to the destruction of the 
roots of the plants infested and the consequent weakening or actual 
killing of the plant. The nature and extent of the injury to corn is 
well illustrated by observations made by one of my assistants, Mr. 
Kelly, in a field near Ludlow, in Champaign county, about ten acres 
of which were almost completely destroyed. By digging up to a 
depth of twenty inches, and searching all the soil belonging to each 
of sixty hills of corn — an area, that is, three and a half feet square 
for each hill — it was found that this badly injured area contained 
an average of 3,460 grubs to the hundred hills, or more than 34 to 
the hill, — a total of about three hundred pounds of grubs to the acre 
of corn. The plants varied in height from two inches to six feet, 
and the total number of ears borne by two thousand hills was 786, 
all small ears or nubbins. 
Prevention and Remedy. 
The subject of preventive and remedial measures was somewhat 
fully treated in my Seventh Report (pp. 127-137), and there is 
nothing important to add to that discussion at the present time be- 
yond a statement of the results of an experiment with pigs as a 
means of clearing the grubs out of an infested field. This experi- 
ment was made in the field above referred to, near Ludlow, 111., ten 
acres of the worst injured part being surrounded with a temporary 
fence, and one hundred pigs averaging seventy-five pounds each, 
together with eight large sows, being turned into the inclosure Sep- 
tember 23. 
By October 13 the pigs had rooted over the whole surface of 
the ten-acre lot, going, in some places, to a depth of ten or twelve 
inches. An area equivalent to twenty corn hills was now examined 
to a depth of twenty inches, with the result that an average of 4.8 
grubs per hill were found, as compared wnth 34.6 per hill at the 
beginning of the experiment — a benefit of 86 per cent, in twenty 
days. The grubs found in the field at this time were usually eight 
inches or more below the surface. 
The pigs W'Cre in this inclosure until October 20, when they were 
removed to another badly injured part of the field, and a final ex- 
amination of the plot was made. In an area equal to ten hills of 
