INSECTS. 129 
spring hatch out minute, active grubs, which 
begin to feed at once on the corn roots, if a new 
crop has been planted on old ground. The 
worms follow these small roots to larger ones, 
into which they burrow, often to the base of 
the plant. When full grown the worms are 
nearly white, a trifle less than half an inch 
long and about the size of ordinary wheat 
straw just below the head. When they reach 
full growth the worms leave the root, crawl to 
one side in the soil, make a cell there, and 
transform into white pupa (grub stage), which 
soon changes into the beetle form. 
This insect has done great damage in our 
corn fields, especially in the Central West. In 
1885 Prof. Webster noted damage to the corn 
crop of Moses Fowler of Lafayette, Ind., 
amounting to 15 per cent of the entire crop on 
10,000 acres—a total loss of about $16;000.* 
A rotation of crops is a satisfactory method 
for preventing damage from this insect, as has 
been demonstrated on a large scale. Wheat or 
oats may be substituted for the corn crop, as 
this insect cannot secure food from their roots, 
they being too woody and tough. The first 
crop of corn on grass or clover sod is not usu- 
ally injured by this pest, although numerous 
cases have occurred where the corn was injured 
on clover sod. 
* Report Indiana Board of Agriculture for 1885, p. 188, 
9 
