Pullman herald. [volume] (Pullman, W.T. [Wash.]) 1888-1989, 1898-01-01
The San lose Scale,

lose scale is spreading over the
Stote and the great amount OF dam
noe occastoned wherever the pest
asins a foothold makes it of the ut
most Importance that orchardists
nse every means in their power to
prevent any further spread and to
Stamp to insect out as nearly as
nossible wherever it already occurs.
MIST orchardists are familiar with
tbe pest bat for those who are not
tbe following descriptions and notes
.ro piven to enable them to recog
pize it and to know something of
its life history.
APPEARANCE or THE PEST.
The insect occurs on all parts Of
the tree; trunk, branches, leaves
and fruit. It's presence on the fruit
is easily detected by the bright red
ying.like spots which always ap.
near. It's presence on the leaves Is
also quite easily detected as the
orayieh color Of the scale shows
quite plainly against the green of
the leaf, especially when they are
massed, as they usually are, along
each side of the midrib and veins
of the leaf. But on the trunk and
branches they are harder to detect
unless they are very abundant.
The scales are very minute, the
largest hardly as large as a pin
head Upon close examination
two different kinds viii be found.
The larger ones, the scale of the
female insects, are circular and fiat,
with the central part pale reddish
yellow and the margin q dark
mottled gray. The others, the
scales of the males, are smaller,
black, circular when young, but
more or less elongated when fully
formed. In the earlier broods the
males are most abundant while in
the latter broods the females seem
to predominant. When the tree is
badly infested they completely COW
er the trunk, branches end twigs,
giving them a characteristic whit
ish mealy appearance. Upon
gently scraping the bark Of such a
tree q yellowish oily fluid will be
seen which comes from the crushed
bodies of the insects; cutting oft a
strip of the bark will disclose a
reddish or brownish discoloration
extending sometimes into the wood.
IT'S LIFE HISTORY.
During the winter the scales as
described above are found on the
trunks and branches of the trees
Some are only about half grown,
others full grown, but all com
pletely dormant. With the first
llow Of sap in the spring they be
gin to feed again and all become
fully matured IN May or June,
when the first brood Of larvae are
produced The larvae are very
minute and can hardly be detected
without the use of lens. Under
the lens they look very much like
little yellowish mites. They move
about actively for a short time and
then settle down on the tender
twigs, leaves or fruit, into which
they insert their beaks and begin
TO suck the juices. Soon they com
mence the secretion of a waXy sub
stance which is the beginning Of
the formation of the sea V covering.
After this they never move about,
and as they grow larger the scale is
enlarged and thickened until it
forms a very effective armor, with
in which a great change takes place
in the appearance of the insect.
The legs and antennae soon entirely
disappear and the females lose their
eyes also. In less than three weeks
from the time of Matching the males
change to pupae and about week
later appear as the fully developed
insect. This is a minute delicate
two winged creature bearing a
straight stoutish appendage at the
posterior end. 1t lives but short
time in this adult condition and
probably takes no part in the prop,
agation Of the species. These are
rarely seen except when bred in
breeding jars.
The females are fully grown
about thirty days after Matching,
andsoon begin to bring forth living
young; one female sometimes Civ
Ing birth to over five hundred young.