Graham guardian., 1912-02-02
FEBRUARY 2. 1912
THE PEACH TREE BoRER

THE PEACH TREE BORER
Peach growing in the Gila valley
Il one Of our most promising indus
tries. So far we have no serious
pests Of peaches established in this
section and it is to be hoped that
through the protective provisions OF
our horticultural law. we may be
kept free from the numerous de-
structive insects which add to the
expense Of growing this fruit in
practically every State in the coun-
try.
The peach tree borer Is OF espec-
ial interest in this section and the
quotations here given from the
writings Of DR.. A. w. Morrill,. the
entomologist Of the Arizona Horti-
cultural Commission. should be read
BY all fruit growers. and especially
by al who are planning to import
fruit for planting.
The first quotation which follows.
10 from the third report OF the
Horticultural Commission:
This insect (Ssnninoidea cxit;nsa)
II rather brilliantly colored moth
in the adult stage. and xsrikingly
resembles wasp in general appear
ancc. The larvae feed under the
bark of peach. apricot. plum and
other stone fruits, freQuentiy COM
pletely girdlina and killing young
trees and greatly impairirg the vitSl-
ity of older trees. The trees are
almost invariably attacked near the
surface Of the ground: rarely far
up on the trunk or more than six
inches underground. Infested peach
trees, except when infected by very
young larvae. are easily detected by
the mass Of gum exuiation which
accumulates at the entrance OF the
jpsects burrow. Plum trees. on
the contrary. exudc comparatively
little gum and the infesta;ion ia icas
readily detected.
Peach borers about three teD.hs
Of IN inch in len2,hlwcre discovered
infesting . shipment Of nursery
stock from Alabams in December,
1910, and ia = shipment from Kan.
sas received during the same month
the worms were oil, nearly full
grown, little less than one inch in
length. During March the worm
Of . peach borer, not over one-tenth
Of an inch in length, was discovered
In . shipment from Missouri, while
many other specimens found In
shipments from Missouri during
March and April were invariably
more than a half-inch in length.
With such a range in size, it is
absolutely impracticable for an in
spector to examine large shipment
Of trees, known to be partly infested
so carefully that he could be reason
ably certain that he has found all
the infested trees. The shippers
and some times the consignees have
requested that infested trees be sep.
srated from the non-infested. but
a. stated above this is impracticable
and It is necessary in such cases to
consider the shipment as whole
infested.
The peach borer is quite generally
distributed in the states east OF the
Rocky Mountains. but has never
been definitely recorded az occurring
in California or Arizona. except on
imported nursery stock. Fortu
nately the importation OF this pest
onnursery stock, even in consider
able numbers, is not always equiv
alent to establishing the species OF
Of giving it an opportunity to be
come successfully established. /
an infested shipment is broken VI
in small lots by selling at retail tn
danger Is much reduced. The i'm
portation of ten live borers in lot
Of q thousand trees for planting il
one block might be repeated man
times without a successful establish
ment resulting. The investigation
Of this pest have shown that tn
adult female lays her eggs within
few hours after she emerges fror
the cocoon, and that If the femal
IS not fertilized by the male mot
within twenty-four hours, infertil
eggs are deposited. Accordingl
the chances for successful estat
lishment Of the pest 10 first OF q
dependant upon the mating of tn
adults, and as both sexes live only
few days at the most. the DANCE
from any particular lot Of light
infested trees may be considered
comparatively small, though n