The herald., 1893-07-26
MORE ON THE STEA-MUE BUG,
Prot. Coquillett Says it Has In
creased Gradually.
A Difference Of Opinion With Mr..
Scott and Mr.. Compere.
The Professor Also Hopss the Steel
Blue Bug May be of Use, But Has
some Doubts-Au Interesting
Expression or Opipion.

gress of the orchus chalybeus in the
Kercheval orchard, the principal topic
among citrus growers has been the SER
viceability of the bug as an extermin-
ator OF the red scale pest.
Faith in Professor Koebele's little
steel-blue antipodean has been revived
and it is the general opinion among the
orchardists that the little lady will prove
to be all that was claimed for her.
A HERALD reporter called upon Prof.
D. w. Coquillett last night and asked
for some expression upon the bug. Pro-
fessor Coquillett is the representative in
California of the division OF entomology
OF the United States department OF agri-
culture. He was found arranging some
specimens of butterflies in boxes, but
readily stopped to discuss the little lady
from Australia.
Prof. Coquillett holds precisely the
same views of the bug that he did last
year. While he says he sees no cause
for all of the recent etir over the insect,
he does not hesitate to acknowledge
that ne believes the chaly beus will prove
to be available allies in checking the
progress of the scale. This is in pre-
else line with his report last November,
which spoke Of the progress and future
of the orchus chalybeus. ''In my opin-
ion," said Prof. Coquillett, s'the work OF
the chalybeus in extermining the peat
is much less effective than that OF the
vedalia.
"Since their introduction into this
country have carefully examined both
OF the varieties on the trees, and had
specimens in my office, and have found
that the vedalia is the more rapid exter-
Ininator OF the scale and its young
breed oftener.
1.-THE vedalia has 10 generations a
year, while the chaly beus has but three.
l had number of specimens of both in
my Office and fed them scale. In the
number of eggs produced the bugs are
about equal, but, "a before stated,
the vedaiia breeds oftener. They also
are the more effective exterminstors.
They eat only white scale, but as soon
as any was given them in the cage they
went to work at that nearest them and
ate every scale in sight, apparently not
stopping until the pest had been exter-
minated.
ION the other hand the lady birds
seemed erratic. They would start at the
scale on one piece of fruit but would
soon stop and go to another piece with
out having finished what they originally
started upon.
"As an illustration of their compare
tive ability as exterminators in the or
chsrds, l will mention the present case
of the Kercheval orchard in the absence
Of the chaly beus and the Dobbins or
chard with the veda liza.
SIN the latter orchard 1 placed two
colonies of the vedalia in 1889, one in
February and one in March. The total
number OF bugs being 85.
BY the end of the following July. 1889,
| Colonel Dobbins wrote and told me thst
those two colonies of vedalia had prscti-
cally cleared his place of the white
scale. He had 35 acres planted to 5000
trees. The vedalia also effectively
cleared the Wolfskill orchard of the
white scale.
"Now, take the case Of the Kerchevsl
orchard and the lady birds. In January,
February and March of 1892 placed
colonies of them numbering $50 bugs on
the lemon tree in that orchard. They
and to feed upon the scale, and at the
end of that time it is discovered that
they have not yet entirely cleaned the
frat tree on which they were placed"
"Did you visit and carefully follow the
progress OF the chalybeus at the Kerche-
val placer"
"Yes. used to visit the orchard and
watch them about every two weeks at
first. During the year 1 did not 60 30
often, being frequently called away upon
other expeditions, but during the entire
time since they were placed there have
carefully followed their progress on the
tree, and also studied their habits by
means of specimens in my Office. When
the rainy season arrived did not visit
the orchard go often, but still kept up
my trips at intervals"
"Did you ever notice any progress ?"
"This progress was very moderate,
and was similar to the growth of ones
brother, inasmuch as it was not particu.
larly noticeable. 1t being evident,
however, that they were making prog
ress in exterminating the scale upon the
tree.
II visited the orchard shortly before
the HERALD published the account ol
the progress OF the lady birds. At that
time saw nothing unusual about them
however, nor have ever noticed any
thing remarkable.
''In my opinion the probable reason
that the bugs were supposed to have
disappeared was this: When the parent
lays the eggs it dies. The bugs
must have laid large quantity of eggs,
the parent dying. AS the eggs are very
difficult to find and the parents were
not to be seen, persons thought that the
colony had periahed. But when the
eggs produced the young it was assumed
that they had suddenly produced in
large numbers. Their growth all along
during the past 18 months has been
gradual, and nothing more"
"What is your opinion of the chaly-
beus ?"
81 believe that it can be a valuable
ally in preventing the spread of the
scale, but thus far it has not yet proved
to he anything like the equal of the
vedalia as destroyer. 1t may yet de-
velop, however, into one OF the best de-
stroyers that can be found.
"The main question among the cr-
chardists down is whether 1t Ia practical
to abandon the artificial fumigation and
spraying of trees for the lady bird.
ITO this say no, for in my opinion
the chaly beus has never yet shown that
it can be depended upon as practical
substitute for the artificial process"
1t is odd that there should be such q
difference of opinion about the steel
blue bug. Mr.. Scott, the horticultural
officer. and George Compere both stated