PRINCIPLES of
PEST CONTROL
What is a PEST?
• Anything that competes,
injures, spreads disease, or
just annoys us
• Most organisms are not pests
Pest Categories
Continuous pest
• Nearly always present
– Requires regular control
Pest Categories
Sporadic, migratory, or
cyclical pest
– Require control
occasionally
Pest Categories
Potential pest
– Don’t require control under
normal circumstances
Pest Control Goals
Prevention
• When the pest’s presence and
damage can be predicted
Pest Control Goals
Suppression
• Reducing pest population to
an acceptable level
Pest Control Goals
Eradication
• Not common in outdoor
conditions
• Indoor is possible
Threshold
• Level of pest population that
action should be taken to
prevent harm
Threshold
Action threshold is based on
visual damage or health
Threshold
Economic threshold is the level
at which cost of harm (yield)
exceeds cost of control
Pest Monitoring
Insects: trapping and scouting
Pest Monitoring
Weed: visual inspection
• Timing emergence
Pest Monitoring
Disease: scouting symptoms
and conditions
Integrated Pest Management (IPM)
Combining appropriate pest
control tactics into a single
plan
Integrated Pest Management (IPM)
Host resistance
• Some species, and some
varieties of species, resist
pests
Integrated Pest Management (IPM)
Host resistance
• Repel pest:
chemicals produced
naturally by plant
Integrated Pest Management (IPM)
Host resistance
• Tolerance: grows vigorous
enough to overcome damage
Integrated Pest Management (IPM)
Host resistance
Physical: some characteristic
makes it difficult for pest
• Pubescent leaf
Integrated Pest Management (IPM)
Biological
• Support predator populations
– Diverse planting
– Native plants
Integrated Pest Management (IPM)
Biological
• Release predators
Integrated Pest Management (IPM)
Biological
• Pheromone traps
Integrated Pest Management (IPM)
Cultural : alter environment,
host, or conditions
• Crop rotation
Integrated Pest Management (IPM)
Cultural : alter environment,
host, or conditions
• Fertilization
Integrated Pest Management (IPM)
Cultural : alter environment,
host, or conditions
• Pruning
Integrated Pest Management (IPM)
Mechanical
• Physical controls
– Handpick
Integrated Pest Management (IPM)
Mechanical
• Screens and barriers
Integrated Pest Management (IPM)
Sanitation
• Removal of debris that harbors
pests
• Diseased foliage
Integrated Pest Management (IPM)
Sanitation
• Overwintering pests
Integrated Pest Management (IPM)
Chemical
• Destroys, controls, or prevents
pests
Chemical failure
• Bad timing
• Wrong chemical
• Wrong dosage
Chemical failure
Resistance
• Pest populations develop
resistance to chemical
• Occurs when the same
chemical is used
• Rotate chemicals