Evening star., 1947-07-02
The Beetles Renew Their Attack
The Japanese Invaders Are Here Again but We Are
Better Prepared to Meet Their Onslaught
By James BirchfeId

The japanese beetles those unWelcome ORR
entail immigrants, are currently making their
annual onslaught upon District parks and
gardens and the farmlands of outlying areas.
From now until late summer, when this
years beetle crop will have consumed count
less shrubs and finally disappeared after lay
ing the eggs for next years ravaging hordes,
the beetles will be the subject of many con-
certed eradication campaigns much conserva-
tion and an occasional frantic phone call
from a gardener who suddenly has discovered
his favorite rose reduced to a mere upright
twig.
The japanese beetle known to entomologists
as Popilia Japonica is Oriental both in dress
and in habit. His brilliant bronze and green
dress is remindful of the costumes of the old
East. His tenacious destructiveness is remind
full of the countrymen from whom he draws
his popular name
AS far as entomologists know, the Japanese
beetle made his unlawful entry into the United
States sometime before 1916. He was first
noted in that year at nursery on the New
Jersey shore, near Philadelphia. Presumably
the beetle grubs had entered the country in
balls of earth on the roots of nursery stock i'm
ported from Japan. Since then his spread
has been rapid.
If We Can Break His Habits.
The very habits of the japanese beetle-his
preference for diet of certain foliage over
others and his yearly life cycle OF egg to grub
to adult beetle-make his eventual eradication
seem hopeful In the Washington area, for
example, his numbers already have been
greatly lowered
The Popillia Japonica is vulnerable to at
tack from four directions. All OF these control
measures may be combined, as is now being
done in Maryland, or a few of the measures
may be used as in the District and some Vlr-
gina areas. Briefly, they include:
l. The use of sprays, such as DOT and the
new benzene hexachlolide, commonly called
$685.
g. Attacking the beetle grubs by spreading
spore dust of milky white disease.
3. Establishing colonies of Tiphia wasps
These insects burrow into the ground, sting
and lay their eggs on the beetle grub, which
in turn is consumed by the Matching wasp
larvae
L. Setting traps. These traps consist of two
types-those that are baited to attract the
beetles and hold them until they may be
disposed Of and those that allow the beetles
to pass out over milky disease spore dust SO
that they may carry the means of their own
destruction back to the breeding grounds.
supplementing these four control measures
Agriculture Department officials are checking
the spread Of beetles to areas not now infested
by inspecting and fumigating airplanes passing
through infested areas, and by checking road
and rail shipments of plant materials.
Reducing the Grubs.
In the District, where DOT sprays and the
spread of milky disease spores are the two
control measures now in use, National Capital
Parks officials have noted q decrease in the
beetle grub count since the first spore dust
was spread in 1940 That year the count on
the Mall was 81 grubs per square foot. Two
years later the count had dropped to eight
grubs per square foot s'
In addition to spreading spore dust park
officials are using DDT sprays this year on low
shrubs around the Pentagon and on elms and
other foliage preferred by the beetles in other
park areas. They do not consider beetle damage
within the District of great economic i'm
portance since it mostly represents dis
ruption OF the scenery in park areas. While
damage to ornamental paintings on private
property may in some years, be rather extern
sive park officials point out that an estimate
of this damage is hard to arrive at.
In the farming areas the picture is different
Serious damage may result to crops such as
corn and fruits unless adequate control steps
are taken In Montgomery County, Md, the
four control measures are being combined this
year in an experimental program that may