Problematic Garden Pests
Aphids
The
first sign of Aphid infestation is wilted looking plants that aren't thriving.
Looking closer, dense colonies of tiny (1/32" - 1/8") soft bodied,
pear-shaped insects are seen, especially on tender growing tips and undersides.
Young Aphids look like miniature adults. And the whole family will be found
feeding together. Aphids feed by sucking plant juices, which is damaging
enough, but the most serious damage comes from the plant diseases they carry.
They
also produce honeydew. This can grow an unsightly, and potentially fatal,
sooty black mold, which hoses off, or washes off with soapy water. Aphids
multiply
so rapidly because they're born pregnant. In fact, there are tiny secondary
embryos inside the first embryos! Add to this the fact that Aphids reach
adulthood in one week and you can see why they can wreak such rapid devastation.
Finally,
there are so many Aphid species that just about every plant has at least
one species that likes it.
To combat Aphids, try these beneficial garden insects:
Aphid
Parasites Aphidius marticariae
Aphid Predators Aphidoletes aphidimyza
Green Lacewings Chrysopa rufilabris
Green Lacewing Larvae Chrysopa rufilabris
Ladybugs Hippodamia convergens
Pirate Bugs Orius insidiosis
Or these other insect-control products
Fleas
It is
important to understand flea biology when preparing to tackle their control.
Adult fleas feed on blood and spend almost their entire lives on their favorite
hosts, cats and dogs. They also can feed on urban wildlife, including racoons,
opossums, skunks, and fox. Females lay eggs that are nonsticky and usually
fall to the ground. After 2 - 5 days, eggs hatch into small, white worm-like
insects. They feed on flea feces (commonly referred to as flea dirt), which
is largely composed of undigested blood. Larvae eventually make cocoons where
they remain for weeks or months. Adult fleas emerge when cocoons are properly
stimulated by warmth, carbon dioxide (breath),or vibrations. A good first
step in the fight against fleas is identifying where they are most common.
This is usually where your pet spends a lot of time, e.g. eating or sleeping.
Because flea eggs don't stick to the animal but drop off, you can expect
a lot of fleas in those areas. You can test for the presence of fleas by
using the white socks test. Walk through your home wearing white socks. The
fleas, attracted by the warmth and movement as you walk, will jump to your
feet and ankles. It is easy to see their dark bodies against the white background
of the socks.
To control Fleas, try these beneficial garden insects:
Predatory Nematodes Steinmatid/Heterorhabitis
Or these other insect-control products
Fungus
Gnats
Fungus
Gnats are small, dingy grey flies, flying around plants aimlessly. If these "flies" are
also seen coming out of the soil around your plants, you probably have Fungus
Gnats. Fungus Gnats can be told apart from Whiteflies, a much more serious
pest, because they're dingy grey instead of pure white. Fungus Gnat larvae,
small worms found in the top inch or two of your soil, feed mostly on organic
debris, fungi, algae, etc. While doing this, they often nibble the roots
of young seedlings. Your plants will often outgrow them, so they may be more
of a nuisance than a real threat to plant health.
To control Fungus Gnats, try these beneficial garden insects:
Predatory Nematodes Steinmatid/Heterorhabitis
Or these other insect-control products
Mealy Bugs
Mealy
bugs are generally the cause of distorted leaves and generally weakened plants.
Clusters of Mealybugs look like a cottony mass. It's only on close examination
that they're seen to be individual, soft bodied, very slow moving insects.
Covered with a fluffy, waxy coating, Mealybugs tend to gather, often at a
crotch or joint. But don't let this quiet-looking crew fool you. Even though
Mealybugs breed somewhat slower than other insects (each generation takes
about a month), they can slowly but steadily build up to quite dense and
damaging populations. General controls, like Pirate Bugs , Lacewings , & Ladybugs
, will eat the young Mealybugs, but Mealybug Destroyers are the best control
for both adult & juvenile Mealybugs.
For Mealy Bug control, try these beneficial garden insects:
Mealy Bug Destroyers Cryptolaemus montrouzieri
Or these other insect-control products
Spider
Mites
Little yellow speckles on leaf surfaces. When you turn a leaf over,
tiny, oval shaped mites, about pin head in size, are scurrying around. Their
eggs,
best seen with a magnifier, will be scattered around at random. Spider Mite
eggs are all perfectly round, the same size, ranging from clear to amber
in color. With larger infestations a fine webbing, crawling with mites, covers
the plant tops. Soon, the leaves are browning and dying. The Two Spot. The "two
spot" Spider Mites are usually yellow/tan/greenish in color, and by
maturity they grow two dark spots on their shoulders, one on each side. The
larger the spots, the older the mite, or the more chlorophyll there is in
the plant species they are feeding on. Spider Mites can float along with
wind currents, or be carried by pets, clothing or infected plant material.
Adult females have the ability to go dormant for a time after the photoperiod
(daily hours of light) shortens, then re-emerge to lay more eggs a few weeks
after the photoperiod lengthens again. That's one reason Spider Mites may
keep reappearing, crop after crop on indoor plants.
To combat Spider Mites, try these beneficial garden insects:
Spider Mite Predators Phytoseiulus Persimilis, Neoseiulus,
Mesoseiulus Longipes
Spider Mite Destroyers Stethours puctillum
Or these other insect-control products
Thrips
You will notice leaf surfaces finely speckled with yellow spots. Later, a
silvery metallic looking sheen may cover leaf surfaces. Not all Thrips create
this sheen. With or without the sheen, you'll also see black specks (Thrip
fecal material). Only on close inspection is the pest itself found. About
1/16" long, thrips can move quite quickly for their size. Many gardeners
report thrips as a small "worm with legs". Larvae and adults look
similar, but adults have wings and can fly. There are too many varieties
and colors of Thrips to try and describe here, but they all feed the same
way - by scraping and rasping at tender leaf surfaces. For control purposes,
the main difference is where they pupate as youngsters. Most Thrips move
down into soil, rockwool or other synthetic growing media to pupate.
For Thrips control, try these beneficial garden insects:
Thrips Predator Mites Amblyseius cucumeris
Or these other insect-control products
Whiteflies
Whiteflies
appear as tiny, pure white "moths" resting on leaf surfaces. When
disturbed, these moth-like flies quickly flutter up, then settle back down
onto plants. Leaves may appear shiny with honeydew. A magnifier reveals clear-white "scales" (the
pupae) on the undersides of leaves. All stages of Whiteflies suck plant juices.
Common species include
the Greenhouse Whitefly & the Sweet Potato Whitefly. It's so difficult
to be certain which species you have, that we advise either consulting your
county
agent to be sure, or simply widening your predator strategy to cover both
species - it's not uncommon to have both pests together. What finally kills
plants with a Whitefly infestation isn't usually the Whiteflies, but a black
sooty mold that grows on their accumulated honeydew. By this stage, there'll
be clouds of Whiteflies. This is the time to rinse any shiny honeydew off
the plants with a strong soapy water spray to prevent sooty mold from growing.
To combat Whiteflies, try these beneficial garden insects:
Whitefly Parasites Encarsia Formosa
Whitefly Predators Delphastus pusillus
Or these other insect-control products
