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Pesky Pill Bugs
 Pill
bugs might be entering
households this fall, due to
the lack of moisture and
cooler weather. Pill bugs
are in the Class Crustacea
so they are closely related
to shrimp, lobsters and
crabs. Pill bugs have seven
sets of legs and their color
varies from dark gray to
white. They get their name
from rolling into a tight
ball when bothered.
Pill bugs are typically
found under rocks, boards,
bricks, trash, decaying
vegetation, logs, or any
area with a high humidity
level. Mulch, grass
clippings, and leaf litter
provide enough decaying
organic matter to allow
these creatures to survive.
They are considered
omnivores feeding on dead or
decaying plants or animals,
so some may feed on the
young roots and shoots of
live plants.
The female pill bug
produces offspring which she
carries in a pouch under her
body, until they can take
care of themselves. Although
mating is common, males can
be produced through
parthenogenesis. An immature
pill bug will molt four or
five times, before becoming
an adult. The immature pill
bugs look like adults except
for size, color and sexual
development. There are
usually multiple generations
a year.
Pill bugs are generally
harmless in landscapes and
they are usually considered
beneficial, since they break
down organic matter.
However, they can become a
serious pest in greenhouses
if large populations exist.
Some Control Options
Non-Chemical
Controls:
Reduce areas of moisture,
especially areas where moss
or fungi inhabit.
Protect natural enemies such
as frogs, toads, and
spiders.
Remove plant debris to
discourage pill bugs.
Chemical Controls:
If infestation exists,
then granules and perimeter
sprays can be applied around
structures and within the
landscape, such as those
containing bifenthrin.
Inviting
Thrips
Indoors
 As
winter approaches, we start
to move our potted plants
indoors. One insect that may
go undetected are thrips.
These insects are very tiny,
almost microscopic and can
be a nuisance since their
mouthparts are able to
penetrate into human skin,
causing a prickly sensation.
Female thrips lay eggs
inside plant leaf tissue,
using a serrated ovipositor
to cut through the plant
tissue. This allows the eggs
and larvae to be well
protected from insecticides
and natural enemies. The
immature thrips will feed on
the plant tissue until it
falls to the ground to
pupate. Thrips undergo a
prepupal and pupal stage
before becoming an adult.
The total length of the
lifecycle from egg to adult
can be completed in about a
week.
Thrips have
rasping-sucking mouthparts
that allow them to cut open
epidermal cells to release
the cell contents that are
then ingested. This causes
the cells to collapse due to
absence of its contents.
Their feeding also causes
discoloration and
deformities of leaves and
petals.
As thrips feed, they
inject salvia into the plant
tissue which allows viruses
to be transmitted. The
viruses they transmit are
Tomato Spot Wilt Virus and
Impatiens Necrotic Spot
Virus. However, the first
instar larvae are the only
life stage that is capable
of obtaining the virus. The
virus then replicates inside
the immature thrips’s saliva
glands as it matures into
adulthood. Once it reaches
adulthood, the thrips is
able to transmit the
disease.
Some Control Options:
Cultural Control
tactics:
Dispose of weeds, trash
or debris to reduce the
thrips population, since
these areas may serve as
overwintering sites for
thrips.
Avoid planting thrips
susceptible plants in areas
close to wheat or rye
fields. Wheat and rye are
both good overwintering
sites for some thrips
species that can attack
landscape plants.
Discard infested plant
materials to avoid infesting
other plants.
Biological Control
tactics:
A natural enemy of thrips
is the adult minute pirate
bug (Orius sp.), which
attacks both immature and
adult thrips. Another
natural enemy is the
Neoseiulus sp. predatory
female adult mite, which
attacks the first instar
thrips and the soil-dwelling
predacious mite, Hypoaspsis
sp, which attack the
prepupal and pupal stages of
thrips in the soil. Also
Beauveria bassiana, a fungus
sold in certain biopesticide
products, is effective at
controlling thrips. This
fungus grows and reproduces
on the host, eventually
killing the thrips in around
7 to 10 days.
Chemical Control
tactics:
Some chemical control
options include products
such as insecticidal soaps,
products containing spinosad,
permethrin, bifenthrin or
acephate applied as foliar
sprays or systemic products
containing such chemicals as
imidacloprid or acephate.
Western flower thrips,
Frankliniella occidentalis (Pergande).
Another
Invading
Cockroach……the
Asian
Cockroach
 The
Asian cockroach, Blattella
asahinai was recently
discovered in Harris County,
in Houston, TX this year. It
is only a matter of time
before this cockroach could
be found in North Texas.
Asian cockroaches resemble
German cockroaches, but they
have different habits. The
Asian cockroaches can be
found both in human
dwellings and in areas away
from human habitats, unlike
the German cockroach that
will only be found in human
dwellings. Outdoors, Asian
cockroaches prefer areas
that are shaded or covered
with leaf litter or grass.
Asian cockroaches are
most active one hour after
sunset and they are
excellent flyers. They will
crawl on the grass blades or
trees and then fly to the
lights at night. If these
lights are close to
structures, then these
roaches could gain entrance
into the buildings. They can
live in large colonies of
30,000 to 250,000 per acre
and they can fly up to 120
feet in a single flight. The
Asian cockroach’s ability to
fly, high reproductive
potential, and outdoor
living habitat will make it
hard to manage this
cockroach.
Some Control Options:
Non-Chemical
Control Options:
Seal any cracks a 1/8
inch or more in the
foundation, walls, ceilings,
and around air conditioning
units, windows, doors,
electrical outlets, pipes or
other openings.
Keep trash and stacks of
firewood away from the home
or garage.
Garbage cans, racks,
platforms or slabs should be
cleaned regularly.
Chemical Control
Options:
Since this cockroach
occasionally invades
structures, indoor and
perimeter applications of
insecticides are effective
such as those containing
bifenthrin, permethrin or
pyriproxyfen.
Adult female Asian
cockroach, Blattella
asahinai Mizukubo, carrying
an egg case (ootheca).
Photograph by: R.W. Baldwin,
University of Florida.
Mention
of commercial products is
for educational purposes
only and does not represent
endorsement by Texas
Cooperative Extension or The
Texas A&M University System.
Insecticide label
registrations are subject to
change, and changes may have
occurred since this
publication was printed. The
pesticide user is always
responsible for applying
products in accordance with
label directions. Always
read and carefully follow
the instructions on the
container label.
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