The Natchitoches enterprise. (Natchitoches, La.) 1888-1965, 1916-08-10
THE HORN-FLY A DANGER.
GUS PEST,
Irritating to Cattle, and Found to Hs
Charbon Carrier-Destroy the
Egg or LarVaI Stage.

The horn-fy was imported from Eu-
rope, and since its arrival in 1887, it
las spread all over the country.
sntomoiogfsts, or those who make
study of insect life, while
hey may recommend some meas
1res to destroy the mature in
sects, usually try to find out how and
here they breed and direct their ef-
orts at killing them in the immature
stages and so prevent their develop
nent. In fact, it is questionable
whether it is possible, by simply de-
;troying adults, to keep pace with
heir multiplication. On the other
hand, IL these insects should be de-
stroyed in the egg and larval, or grub
itages, material reduction in their
rumbers might be brought about, even
1 the adult flies themselves should be
left alone, The important question
therefore is, where do these horn-fiies
breed? According to the best au-
thorities, this fly lays its eggs singly,
md usually upon their sides, on the
surface of wet cow manure. So far
s is known, they are laid upon no
'ther substance, and never upon old
lroppings. The moment the manure
5 dropped, swarm of flies dart from
le animal to the manure and remain
here a few seconds, or minute at
he most, during which time many
Ggs are deposited. Egg laying is
hiefy during daylight and most
bundant during the warmer morning
ours. After the larvae, or grubs,
'atch, they descend into the manure,
although remaining near the surface.
The pupa, or dormant stage of the
insect, is found in the ground un-
lerneath the droppings. The time
yhich elapses from the egg to the
,dult stage, or fly, is from about ten
o seventeen days.
The fresh COW droppings, then, are
he places on which these flies lay
heir eggs, and where the different
ages of the insect develop until the
ull-fedged insect emerges The most
ractical method of control. therefore,
tould be the direct treatment of the
anure to destroy the grubs and pu-
ae, and so limit the number of flies
oming to maturity. and one of the
est agents to apply to the fresh drop
ings is lime This may be quite
7actical around buildings and yards
coupled by cattle, but somewhat i'm
ractical out in the open fields and
3nges, elthough it might be possible
carry out this method even under
r,ch conditions, IL the manure around
ne places where cattle are in the
,abit of congregating, under shade
rees, and the like AT best, it
a trouble, but it Is not possible
20 secure results without some trou-
lie, and if we ever expect to reduce
he numbers of these pestiferous in
acts, we win have to get after their
1reeding places and AAstroy them
here.
The arsenical sorutron uE-u m the
Tipping vats destroys large numbers
of these flies, and there are a num-
her of sprays used to repel them
from the animal, such as fish and
coal oil emulsions, the various repel-
lants on the market. etc. However,
none Of these will effectually eradi- I
cate the horn-Ay, while a combination
of both measures would no doubt give
the most satisfactory results. In ad-
dition to its irritating effect on cat /
tie, the hera-fy has been found to be
q carrier Of charbon infection.
w. H Dairymple,
louisiana State University. /