The Corvallis times. (Corvallis, Or.) 1888-1909, 1906-03-16
Three Billion.

In one Season From one Female
Things About San Jose Scale.
1t is possible for the offspring of
one female San Jose scale to multi
ply until they reach a total of more
than 5000, ooo, 900 young insects
in single season: Such is the fact
brought out in new bulletin about
to be issued by Prof. Cordley.
Concerning the prolific multiplica-
ton of its species, the bulletin says:
Each female of the over-wintering
generation is capable under favor
able conditions :tof producing ap-
proximately 100 young. In the
course aof-Y but one month, these
reach maturity and the females be-
gin to produce another generation.
There are thus produced some four
or five generations during the sea-
son. Under supposedly favorable
conditions, single female of the
later generations have been observ-
ed to produce approximately 500
young Basing their estimates up
on breeding cage observations, DR..
Howard and. Mr.. Pergande have
shown that it would be possible,
under the most favorable conditions
for the progeny Of single female
to produce the astonishing number
of 3,216, ,oso, 400 individuals in a
single season. Should each OF these
scales reach the largest size, one
tenth Of an inch, and were they
placed side by side, touching each
other in all directions, there would
be enough of them to cover approx
imately five acres of surface. - -sz
The bulletin adds that on account
of the struggle for existence of
organism against organism and Of
other adverse emergencies. it is not
likely that this aggregate in propa-
CATION is ever reached. It might
be added that this is notably true
now when so many men are at
large in Benton orchards and door
yards with spray pumps in their
| hands, lime, sulphur and salt
solutions in their tanks and blood
In their eyes.
The bulletin also contains color
ed illustrations of fruit infected
with the scale, as we'll as by pic
lures of the scale itself, from which
it is easy to recognize the pest
when it is encountered in the or.
chard. The appearance of the
pest is also minutely described as
follows:
1.-The mature scale are grayish in
color, being usually. but not al,
ways, lighter in color than the bark
to which they are so closely attach
ed. The immature, half grown
scales, which may be found with
the mature ones, are at the present
time somewhat darker In color
The mature female is nearly circu-
lar in shape, is approximately one
sixteenth of an inch in diameter,
and each is somewhat raised in the
i center to form a slight protuber-
ance or nipple, which is lighter in
color than the rest of the scale. II
this scale is carefully examined
with a small magni6er, several con-
centric circles may be observed be-
tween the nipple and the outer
edge; and if it be carefully lifted
with the point of a pin or knife,
there will be- revealed minute,
bright yellow object, the insect
itself. On badly infested plants
the young scale settles wherever
there is room to insert a beak into
the bark, and as they increase in
size they become much crowded
and overlap, giving the appearance
of gray scurvy deposit on the
bark"
The bulletin is very interesting
even to those who are not at war
with the scale. To those who are
engaged in a fight to exterminate
the pest, Prof. Cordley's little pam
phlet Is as valuable as it: is attract
i've. 1t can be had free on app1ica-
ton at the college It gives full
directions concerning sprays and
spraying. sadi
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