The San Francisco call., 1903-12-28

grown from Seeding trees or propa-
gated from locally grown trees and
were free from pests. The orange and
lemon trees were bright and free from
smut. The bright and thrifty condition
of the trees induced our pioneers of
the fifties and sixties to bring or send
for new varieties. The soft brown
scale was introduced into the orchards
and gardens of Los Angeles and spread
with alarming rapidity. Orange trees
were killed by that scale and orange
planting was stopped. Years passed
and the parasites of this scale were un-
Intentionally introduced upon other
plants and now this scale is not classed
as a pest unless where the constant
presence of ants prevent the parasites
from accomplishing their destruction.
The parasites of the soft brown are
both chalcid flies.
One is parasitic of the small scales
ard the other attacks the full grown
scale. One deposits but one egg in each
scale and the other from one to eight,
and each egg develops into a maggot
and then into perfect fly all under the
scale. They are exceedingly small in
sects, each with four wings, six legs
and two antennae The orange growers
overlooked such diminutive insects and
their valuable work was ascribed to
some mysterious disease, or, as several
growers stated, the scales had run
their course and were naturally dying
out"
BLACK SCALE KILLER.
Tho payt cariO,s ccoIo that v,oS IN
troduced was the black scale" This
is a more general feeder, and besides
olive trees it also attacks orange, lemon
lime, plum, peach, apricot, pepper, OLE
ander, crataegus, pittisporum, abutilon
pelargonium, photinias and a variety Of
wild shrubs and weeds. We have a
native internal parasite that in some
seasons destroys from twenty-five to
seventy-fve per cent, but as each scale
produces from 1900 to $500 eggs, it will
be readily seen that the parasite alone
could not cope with such a pest, as it
has but one generation each year.
The black ladybird was introduced
from Australia by 4.lbert Koebele when
collecting beneficial insects for the
State Board of Horticulture of Califor-
MIA. Twenty of these valuable beetles
reached us alive, and they have been
of great service in cleaning out the
black scale in the coast regions.
In the southwestern portion of Ala
media County William Barry, Horticul-
tural Commissioner of that portion of
the county, made a canvass in Wash
ington Township of the orchardists
having five acres and more and learned
that since the introduction of this bene-
fetal insect nine years ago they have
saved over $171 900 in disinfection. The
"black ladybird" breeds the year round
and destroys the eggs, larvae and adult
"black scale" Unfortunately they do
not appear to thrive away from the sea
breeze. At Ellwood, in Santa Barbara
County, Mr.. Cooper before the intro
duction of this Iadybird spent from
$4,000 to $4,000 per annum in spraying his
orchards with kerosene emulsion. Since
then he has relied upon the ladybirds
and his trees bear better and cleaner
olives.
THE COTTONY CUSHION.
The next serious pest introduced was
the "cottony cushion scale" This came
on trees brought into Menlo Park from
Australia in 1868 and in the eighties it
had spread over great portion of the
state and it was such destructive in
sect that the orange industry was
threatened.
Two years after it attacked the Shorb
groves at San Gabriel. 1t reduced the
crop from fifty carloads per annum to
six cars of inferior oranges on that es-
tate alone. The expensive fight made
against this pest in California with
sprays, fumigators, etc, resulted in
more advance in the study of economic
entomology than any other one thing
and was the cause of our belief that ma
ture had a more efficient and cheaper