The Rich Hill tribune. (Rich Hill, Mo.) 1903-1911, 1908-01-09
pAaAsIras VI. wAlTE aaua.
What Illinois Expert Has Discovered
Concerning Work Of Former.

Concerning Work Of Former.
Tho Illinois state Cutomologist. Dr..
s. A. Forbes. OF Urbana, has done
much tn studying the parasites that
destroy the white grub, and the fol
lowing items from Wis ONCE Indicate
something OF the beginning that has
been made In solving one OF the vital
aud urgent problems OF the %farInor
The common grub wasp Criphla) Is
much the most important insect enc.
my OF the white grub, Il Is a slender,
jet.black insect usually two-thlrds Of
an inch long. with wings either clear
OF tinged with dusky yellow.
Il enters the ground In search OF the
grubs. follows them up e. their bur.
rows and lays on the back OF each
grub a single egg. which matches into
a footless maggot.like larva which ad-
heres TO the surface OF the grub. pune
lures its skin. and sucks its blood for
a time, but finally eats Il up.
These maggots have Teen known to
destroy. under favorable circum.
stances, the entire grub population Of
a badly infested field. The method of
this insect and the main facts Of its
life history have been worked out In
Or. Rorbes' %insectary the past two
years by j. J.. Davis and J. A. West.
from cocoons and infested grubs sent
in by f. o. G Kelly from fields at FL.
licott. m.
The wasp attacks the grub and q
violent struggle ensues until the for
mer stings her prey. temporarily
paralyzing &, and then smcars a yiscid
nuid 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 and has been fully observed q
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 seven to ten
days and TO- takes the maggot about
two weeks Il get its full growth. j,
doubles its size the last two days.
when it deyours the body of It's host
The f%ullgrOwn magEct is two-thirds
to four-hfths OF an inch In length.
In several cases an abundance OF It's
cocoons were found in the ground. in
dicating an enormous destruction OF
white grubs. No doubt this wasp Is
an important agent. in chccking-de
]structiye uprisings OF grubs
a little tachinir ny is another para
site Of the grub The adult is a large
hlackish-gray ny with a genera.
resemblance TO the common large
blow fly. Another parasite Is the
young of a large. slender bodied. dart
red ichncumon as. SIN another is .
bee-ny covered with erect yellow fur.
Mr.. West discovered May.beetle,
dropping To- earth trying to rid them
selves of adult flies that were clingln,
20 them and apparently thrusting egg,
into their backs. The effect was tostet
IN hreeding-caees. The beetles 81
treated lived for some days and ther
began TO die. dipterous murgots beiul
found Ia the body. These flies wer,
also seen among the May beetles o.
the trees az night.
Nothing has been done TO test %,
possibility OF collecting and dlstrlbut
ing parasites, other than those OF con
tagious diseases, and the latter subjec.
has not been worked out 10 final con
illusions So IL is seen that the para
sites alone oner a large field for IN
vesugation with a view 10 the destruc
tion Of white grubs.