Transcript Turfgrass IPM - Nc State University

Turfgrass IPM
• Integrated Pest Management or
• Intelligent Pest Management
• Ecosystems are composed of beneficial and
detrimental organisms. Ideally want
selective control of the detrimentals!
• The use of all control measures to reduce a
pest population or minimize its impact.
Cultural, biological and chemical controls
are all included.
A New Philosophy
• Reduces dependence, but does not eliminate
or preclude the use of pesticides
• Site specific
• Relies on tolerance thresholds rather than
elimination
• Cost effective
• Good for the environment
• Good for public image
• Good for the industry
The Basics
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Site assessment
Pest profiles
Monitoring
Setting thresholds
Stress management (the turf’s)
Identifying management options
Evaluation
Site Assessment
• Of entire area
• Maps of irrigation, drainage, trees, soil
types, elevations, shade patterns, traffic
patterns, surface waters, structures, beds,
and turf species. Also note problem areas,
pest history.
Pest Profiles
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Pest ID
Symptoms
When and where, life cycle, biology
Scouting and monitoring, threshold levels
Cultural control practices
Biological control options
Chemical control options
Monitoring
• What does damage look like?
– Patches? Size? Do they coalesce? Color?
Lesions on the blades? Is turf intact, rooted?
• Where does damage occur?
– All or one species? All or one area? Shade?
South facing slopes? Wet soils? Dry soils?
Dead air?
• When does the damage occur?
– What are the associated conditions?
Monitoring
• Need to monitor before and after control
treatment to assess effectiveness
• Evaluate the success or failure. Was
weather involved? Timing? Incorrect ID?
Improper selection of control/chemical?
Improper management?
• Know life cycles to avoid monitoring
during wrong seasons. Saves time and $$$.
Monitoring Techniques
• For insects (grubs mainly)
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Soil samples
Soap flush
Flooding
Traps (pheromone, light, pitfall)
• For weeds
– Transect lines
– Random samples using frame
– Daily collection, mapping
Monitoring Techniques
• For diseases
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Active mycelia
Disease symptoms
Disease clinic
Disease often in same locations, map!
• Nematodes
– Composite 4” soil cores, seal in plastic, send to
laboratory
– Take samples from site with/without symptoms
Setting Thresholds
• Cannot rid a turf of pests, so need to
establish limits for their presence and
activity
• Based on aesthetics, use, expectations,
species, time of year
• Also on whether control measures are
available, and costs of control
• Site specific
Controls - Stress Management
• Mowing at proper height to maximize
photosynthesis
• Water management (rain, irrig’n, dew, ice)
• Water quality (salts)
• Turfgrass selection
• Fertilization
• Soil management (pH, compaction, thatch,
salinity, nutrition)
Biological Controls
• The use of living organisms, or products of
living organisms to suppress pest
populations or activity
• Natural ecosystems contain checks and
balances, predators and prey, which keep
things on an even keel - few epidemics.
• Many insect pests have been introduced or
imported from overseas, without their
natural enemies.
Biological Controls
• Most fungi are not pathogenic, and many
are critical to the normal health of a soil
ecosystem. Some produce natural products
which inhibit other fungi, including
pathogens. Isolating these materials can
lead to natural fungicides, eg. Heritage
• Adding organic matter to soils usually
stimulates general microbial activity, which
can inhibit turf pathogenic fungi
Insect BioControl
• Parasites, usually flies or wasps, lay eggs in
their host. The larvae hatch and feed on the
host. Often host specific, but difficult to do.
eg. Parasitic wasps on white grubs
• Predators which seek out and attack host.
Usually adults. eg. Lady bugs, preying
mantis
Insect BioControl
• Pathogens, eg. Entomopathogenic
nematodes, which enter host and transmit a
toxic bacteria.
• Bacteria which produce toxins specific for
some insects. The BT toxin is the industry
standard, and can be applied in living
bacteria or in transgenic plants.
• Several fungi attack certain insects but not
plants or animals. They are not always
stable in the soil, however.
Insect BioControl
• Insect growth regulators. Juvenility
hormones repress development and prevent
the insect from growing and reproducing.
These are usually species specific
• Some growth regulators interfere with
molting. These may be more general, and
can target beneficial organisms.
• Endophytes are fungi which live inside the
turfgrass plant, between the cells, and
produce toxins to insects (and livestock)
Problems with Biocontrol
• Few success stories (Heritage and related
fungicides the exception)
• Introduced organisms often fail to establish
or survive long enough to impact target host.
• Organisms are easily damaged prior to
application
• Shear numbers and diversity of native
organisms may exceed introduced organisms
Chemical Control
• Decisions need to be based on:
– environmental risks
– timing for optimum control
– pesticide characteristics
• mobility
• persistence (many ways to lose activity)
• pH sensitivity
– spectrum of activity (other organisms?)
– resistance management
Chemical Control Risks
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Runoff
Leaching
Volatilization
Removal in/on clippings
Dislodgeable residues
Human toxicity - chronic and acute
Toxicity to non-target organisms