Louisiana Yards and Neighborhoods Manage Yard Pests Responsibly

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Louisiana Yards and
Neighborhoods
www.lsuagcenter.com/lyn
Manage Yard
Pests Responsibly
Pesticide Consequences
Synthetic chemical pesticides were introduced in
the 1940s to control agricultural pests;
unfortunately, there were some unexpected
consequences…
• Hazardous to humans
• Residues in food
• Environmental impacts
• Pests becoming resistant
• Expensive to use
Cycle of Pesticide Dependency
Many chemical pesticides are broad
spectrum, killing not only targeted pests but
beneficial organisms that serve as natural
pest control systems.
NO Natural Controls
Indiscriminate
mortality - pests
and beneficials
Dependence on
chemical pesticides
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In the days following a
pesticide treatment, pests
reproduce faster than
predatory insects. By killing off
beneficial insects, pest
populations flourish.
Tolerance
Some damage to plants is
natural. Don’t strive for a
pest-free yard; instead,
decide on a realistic
threshold of damage.
What Is a Pest, Really?
Pest: plant, animal or other organism that is
out of place.
 Diseases, weeds, insects,
reptiles, mammals,
arthropods
 Of all insect species
in the world, less than 1%
considered pests
Am I a pest? This depends on where I am
feeding, in the yard or the butterfly garden.
Aphids
Honeydew
CORNICALS
• Piercing-sucking mouthparts
allow aphid to feed on plant
juices.
• Causes stunting and curling
on new terminal growth.
• Excrete honeydew.
Parasitized aphid mummy
Watch for pinholes,
indicating parasitism
by a wasp.
• 2 types: soft and armored scale.
• Piercing-sucking mouthparts allow
it to feed on plant juices.
• Damage: chlorosis and leaf drop.
• Soft scales excrete honeydew.
Sooty mold (shown here) is a fungus that
grows on honeydew excretions.
Whiteflies
• Piercing-sucking mouthparts
allow it to feed on plant juices.
• Infest lower leaf surfaces.
• Damaged leaves appear spotted.
• Sooty mold.
• Transmit plant viruses.
Immature
whiteflies also
damage plants.
Spider
Mites
• Tiny, with 8 legs
• Piercing-sucking
• Mites, eggs, cast skins and
webs visible with hand lens
• Leaves appear stippled
• High infestation rates lead to
mite migration
Thrips
• Feed on flowers and young
foliage
• Found on the underside of leaf
• Excrement is shiny-black
• Transmit plant diseases
• Damaged plants appear flecked
or bleached
• Cause leaf and flower
distortions and bud drop
Caterpillars
• Larva of butterflies and
moths.
• Some have venomous spines.
• Most are foliage feeders;
some are borers.
• 1 to 4 abdominal prolegs.
Sawflies
• Look like caterpillars
• Foliage feeders
• Proleg on each
segment of the
abdomen
• One simple eye on
each side of head
Mole Cricket
• Grass root feeders
• Tunnel turf and dry out
grass roots
• 3 species in Louisiana
• Front legs flattened and
adapted for digging
Chinch Bugs
• Like hot, dry weather
• Feed on many grasses;
prefer St. Augustine grass
• Piercing sucking mouthparts
• Produce odor when crushed
Red Imported Fire Ants
• Infest 330,000,000 acres
• Inflict painful sting
• Build unsightly mounds
• Can be beneficial
• 60,000 to 100,000 per mound
Environmental Stresses
Many environmental effects mistakenly
treated as pest problems
• Drought
• Nutrient deficiency
• Variations in pH
• Mechanical damage
• Cold damage
• Excessive water or fertilizer
Herbicides injured this
tomato plant.
Integrated Pest Management
(IPM)
 IPM is the coordinated use of pest and
environmental information and available
pest control methods…
 To prevent unacceptable levels of pest
damage by the most economical means…
 With the least possible hazard to people,
property and the environment.
Principles of IPM
Sustainable - using a resource so that the
resource is not depleted or permanently
damaged
Prevention
Cultural Practices
Biological Methods
Physical Methods
Chemical Methods
Prevention
Our most sustainable pest control method
involves avoiding the introduction of pests
(into our country, state or yard).
• Buy pest-free plants.
• Select plants adapted to your yard.
• Select resistant varieties.
• Avoid notoriously problematic plants.
• Properly install and maintain plants.
Key Plant, Key Pest
Some key plants are likely to be infested by
key pests. For example, Azaleas are commonly
infested by lacebugs, particularly if the azalea
is planted in a sunny location.
Scouting
Monitor plants routinely to aid in early
detection of an insect, disease or other
problem. Look for:
• Favorable conditions for pests
• Signs and symptoms of pests
– Damage to the plant
– Pests (leaf spot, leaf curl,
feeding)
– Frass - insect excretions
• Presence of natural enemies
Cultural Practices
We also can avoid problems with insects and
diseases through proper design, installation
and maintenance.
Stressed plants are more
susceptible to attack, like
this Chinese Elm with
crowded roots.
Water Wisely
• Water during the early morning, when
leaves are already wet.
• Avoid overhead irrigation of woody
ornamentals.
Many foliar diseases gain entry into plants
through the water remaining on leaves.
Biological Control
The use of living organisms to control pests:
• Predators
• Parasites
• Pathogens
Lady beetles and their larvae feed on aphids
and other soft-bodied insects. They are
commercially available in bulk.
Predators
Predatory mite
In general, predators are larger, faster,
more aggressive and present in
relatively fewer numbers than their prey.
Bigeyed bugs are raised
commercially to control
whiteflies, spider mites,
aphids, caterpillars & thrips.
Assassin bug
Predators
• Can kill large numbers of prey
• Generalists, rather than
specialists
• Often social creatures (wasps,
ants)
Wasps also can be pests if they
congregate in the wrong places,
like inside your home.
Parasites
• Very specialized
• Often small
• Look for:
– A trail of bodies
– Exit holes
– Color changes
Healthy aphids
Parasitized aphids
Pathogens
• Naturally occurring insect diseases
– Bacteria, fungi, viruses and protozoa
• Often specific to host
• Lag time - may take a few days to provide
control
Bacillus thuringiensis
is a bacterium that
kills caterpillars
when ingested.
Attract Beneficial Insects by:
• Not using harmful pesticides
• Providing food
– Nectar and Pollen
– Plant diversity
• Providing shelter
– Enhance vertical layers
Food for Thought
Many herbs and fragrant flowering plants
attract natural enemies

Gaillardia

Clover

Milkweeds

Cilantro

Goldenrod

Dill

Echinacea

Fennel

Sunflower

Mustards
Clover also fixes
atmospheric nitrogen
into a form available to
other plants.
As A Last Resort….
Sometimes, major pest damage reaches a level
that is unacceptable to the observer. When all
previous management efforts have been
ineffective, individuals may wish to apply:
• Physical methods
• Chemical methods
These are the least sustainable methods
discussed because they are labor intensive,
and often require repeated treatments.
Physical Management
• Remove pests by hand.
• Remove infested parts.
• Establish barriers to
prevent pest access
to plants.
Yellow sticky paper attracts whiteflies and other
insects. These traps help to monitor pest
populations in greenhouses.
Chemicals
• Choose least harmful pesticides.
– Use selective pesticides rather than
broad spectrum killers.
• Spot treat where pests are
abundant, rather than the
entire yard.
• Follow pesticide label
instructions carefully.
Management Strategies
• “Sap suckers”- (aphids, soft scales, mealybugs,
whiteflies, spider mites)
– Biological controls
– Soaps and oils
• Caterpillars – Bt
• Plant chewers - (grasshoppers, beetles, leaf
miners)
– Use a proper insecticide if damage warrants
action
For More Information on
IPM STRATEGIES
Visit: www.lsuagcenter.com
Features: newsletters, presentations, news
releases, photo galleries, videos, publications,
diagnostic clinic, listserv, links and more!
Further Reading
www.lsuagcenter.com/lyn
•
Louisiana Lawn Best Management Practices
Pub.# 2940
•
Insect Pest Management Guide
•
Turf Maintenance for Athletic Fields Pub.# 1989
•
Managing Imported Fire Ants in Urban Areas
Pub.# 2817
•
Broadcast Baits for Fire Ant Control
•
Bugs, Bugs, Bugs Newsletter
Further Reading
(cont’d.)
• Wildlife Newsletters:
www.lsuagcenter.com/en/environment/wildlife/
louisiana+wildlife+news.htm
• Plant Disease Control Guide
• Turf Diseases
• Weed Control Guide
Thanks for Your Attention!
Special thanks to the following reviewers for their valued
contributions:
FL114 ELM Design Team and the FYN Subcommittee
Institute of Food and Agricultural Sciences, UF
Agriculture Education and Communication Department
Environmental Horticulture Department
Entomology and Nematology Department
Soil and Water Sciences Department
Florida Cooperative Extension Service in: Alachua, Broward, Clay,
Hillsborough, Lake, Miami-Dade, Orange, Pinellas, Sarasota and Volusia Counties
Florida Organics Recycling Center for Excellence
The Center For Wetlands, UF
United States Department of Agriculture
FL Department of Agriculture and Consumer Sciences: Division of Plant Industry
Louisiana Yards and
Neighborhoods
www.lsuagcenter.com/lyn
Manage Yard
Pests Responsibly
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