Ill 
INJURIES TO CORN AND OTHER VEGETATION. 
The injuries of the American white grubs to corn may begin 
as soon as the roots of the young plant become large enough 
to attract the attention of a hungry insect, and may range- 
according to the age of the plant, the kind of weather, and the 
age and abundance of the grubs—all the way from a slight and 
temporary retardation of growth to an immediate and complete 
destruction of all the corn. An early loss of the tap root ex¬ 
poses the plant to severe suffering by early drouth, and it is 
often so reduced in vigor from root injury that it fails to form 
brace roots at the proper time, and hence has so slight a hold 
up^n the earth that it cannot keep itself erect or recover itself 
after prostration by a windy summer storm. 
In any case where the plant is yellowed, or dwarfed, or killed 
outright,—especially if these appearances be most marked on 
the higher, lighter parts of the field,—the presence of white grubs 
may be suspected. 
As the roots of an infested plant are evidently eaten away, 
injury by the white grub is not easily mistaken for any other, 
and the presence of the conspicuous insects themselves, in the 
earth among or beneath the roots, will commonly confirm the 
diagnosis. If they are not thus found where other evidence 
points to them as the cause of the injury, they may frequently 
be discovered by digging down a foot or two in the worst-in¬ 
jured tracts. 
As a fair illustration of the extent and general effect of a se¬ 
vere attack on corn, our observations of their work in a twenty- 
acre field near Champaign, Illinois, are worthy of detailed re¬ 
port. This field of rich,' black land had been heavily fertilized 
with straw-pile manure and seeded to timothy in 1884. It was 
pastured continuously until 1888, when it was led for hay, 
yielding a good crop of clean timothy that year. The sod was 
broken in the spring of 1889, and planted to corn May 10, im¬ 
mediately after breaking. This first planting was taken by web 
worms and cutworms, but the second grew well, and promised 
an excellent crop until about tasseling time, when the owner 
noticed that much of the corn had a yellowish and unhealthy 
appearance, and that it blew down readily when the ground 
was web. These fallen hills pulled up easily, and the roots had 
a stubbed appearance, as if cut off near their origin. A search 
in the earth where the corn had stood commonly yielded six to 
twelve white grubs to a hill. The crop on two or three acres of 
the highest land was a total failure, and the yield was light on 
the lower ground. 
f-'The following year (1890) the field was plowed April 28 and 
planted again to corn, although an abundance of grubs were 
noticed when the plowing was done. Several hundred were, in 
fact, collected by us April 28 for breeding-cage experiments, 
nearly all belonging to the species L. rugosa. An estimate baaed 
