The citizen. [volume] (Berea, Ky.) 1899-1958, 1908-01-09
PARASITES VS.. WHITE eeus.
What Illinois Expert Has Discoveries
Concerning Work OF Former.

The Illinois state entomologist, DIR.
s, A. Forbes. Of Urbana. has done
much in studying the parasites that
destroy the white grub, and the fol-
lowing items from Wis Office indicate
something OF the beginning that has
been made In solving one OF tho vital
and urgent problems OF the farmer.
The common grub wasp (Tiphia) Is
much the most important insect enc
my OF the white grub. IL Is n slender.
jet.black insect, usually two-thirds OF
an inch long. with wings either clear
or tinged with dusky yellow.
IL enters the ground In search OF the
grubs, follows them up In their bur
rows and lays on the back Of each
grub single egg. which matches into
footless maggotllke larva which ad-
heres to the surface OF the grub. pune
lures its skin, and sucks It's blood for
a time. but finally eats II up.
These maggots have been known to
destroy. under favorable circum-
stances. the entire grub population OF
a badly infested field. Tho method Of
this insect aud the main facts OF Its
life history have been worked out In
DR.. Rorbes' insectary the past two
years by J. ]. Davis and J. A. West.
from cocoons and infested grubs sent
In by Il. o. q. Kelly from fields at FL
licott. III.
The wasp attacks the grub and .
violent struggle ensues until the for
mer stings her prey. temporarily
paralyzing II. and then smcars viscid
fluid upon the back OF the grub not
far behind the head. and deposits her
egg ON this sticky surface.
The operation occupies several min.
utes aud has been fully observed a
number OF times Several white grubs
found In the field had these parasites
on the under side OF the body between
the thoracic legs.
The egg matches In s,'ven 60 ten
days and Il takes the maggot about
two weeks to get It's full growth. IL
doubles its sire the last two days.
when Il devours the body Of Its host.
The full-grown maggot In twothirds
TO four.nfths OF an inch in length
In several cnses an abundance of It's
cocoons we're found In the ground. In.
dicaiing an enormous destruction OF
white grubs. No doubt this wasp Is
an important agent I'm checking de
strucuve uprisings Of grubs.
| \ little tachinlr ny Is another para.
site OF the grub. The adult Is a large
I hfucLigh.orny Nv with n general
resemblance 10 the common large
blow ny. Another parasite Is the
young OF large. slender.bodlcd. dark
red ichneumon ny. sim another is a
bee.ny covered with erect yellow fur.
Mr.. West discovered May.bcotics
dropping to earth trying to rid them.
selves OF adult flies that were clinginE
10 them and apparently thrusting eggs
into their backs. The effect was tested
la breedingoagcs. The beetles so
treated lived for some days and then
began 10 die. dipterous maggots being
found In the body. These flies were
also seen among the May.oeeties on
the trees at night.
Nothing has been done 10 test the
possibility OF collecting and dlstribut.
tagious diseases. and the latter subject
has not been worked ont 20 final con.
illusions. SO Il Is seen that the para.
sites alone offer a large field for In.
yostigailon with a view 20 the dcstruc.
ton Of white grubs.