High Tunnel
Fruit and Vegetable Production
 Identify the components of integrated pest
 Recall the importance of integrated pest
management to growers and the environment.
 Discuss a variety of control tactics available to
manage insects, diseases and other pests.
High Tunnel and Insects
 High tunnels create a unique environment
 May
lead to different insect and disease pests than
greenhouse or field production
 Even with these differences, the generalities of
Integrated Pest Management apply
Integrated Pest Management
 Commonly known as IPM
 Common-sense, holistic approach
 Uses knowledge of plants, pests, and the
environment sensibly to reduce number of pests.
 Reducing
pests before unacceptable damage is done
 Uses a combination of control tactics
 Prevention
 Monitoring
 Control
 Use knowledge of past and potential pests to avoid
future problems
 Prevention Activities:
 Choose
resistant and adapted species when available
 Plant according to best management practices
 Plant disease- and pest-free transplants and seeds
 Use sanitation practices
 Irrigate and use mulch to minimize plant stress
 Fertilize according to need
 Inspection, detection and scouting
 Find pests and diseases early
 Use of trapping devices and visual inspection
 Provides information to aid in pest control decision-
making process
 Inspect plants in high tunnel at least twice a week
 Count
 Specific
 Take
locations and specific plant parts
good notes and observations
 Pest,
crop, number found and stage of insect growth
Control Techniques
 Four different types of control techniques
 Cultural
(Prevention Techniques)
 Biological
 Mechanical (or Physical)
 Chemical
 The four management tactics can be used alone or
in combination
 Ultimate
goal is to reduce or prevent pest injury
Control Techniques: Cultural
 Horticultural practices that limit pest populations or
reduce the amount of damage that pests might
 Essentially the same as prevention measures
 Control techniques include:
 Maintaining
plant health
 Making proper plant selections
 Choosing resistant varieties
 Using crop rotation
 Other practices that maintain healthy, vigorous plants
Control Techniques: Biological
 Also known as bio-control
 Uses living organisms to suppress or limit pest
 Keeps populations down, does not eliminate pests
 Low
level of injury expected
 Acceptability depends on tolerance level
 Use of “natural enemies”
 Organisms
that attack pests
 Three categories: Predators, Parasitoids, Pathogens
Control Techniques: Biological
 Two main ways to use biological controls
 Augmentation
 Release
of specific beneficial organisms for control of
existing pest population
 Conservation
 Conserves
natural enemies that are already present
 Reduce use of broad-spectrum pesticides
 Pathogens
 Microorganisms:
Bacteria, Fungi, Viruses, Nematodes
 Weaken and kill pests by creating disease or infection
Control Techniques: Mechanical/Physical
 This control method separates the pest from the
crop by means of a device or action
 Actions:
 Handpicking
pests directly from plants
 Forceful water sprays to dislodge aphids
 Pruning to remove diseased or infested plant material
 Install insect screening over vents and side walls
 Excludes
larger insects
Control Techniques: Mechanical/Physical
 Screening reduces airflow, increases temperatures
 Often
overlooked when growers are unaware
 May reduce airflow by 5-10% with active ventilation
 May result in 45% ‘wind reduction’ in passively
ventilated tunnels – raised air temperature of ~5°F
 Increase in temperatures could be partially offset by
using peak vents or exhaust fans
Control Techniques: Mechanical/Physical
 Screening
 Standard
window screening is an economical choice
 Must
be cleaned occasionally
 Does not completely restrict influx of pests, reduces
 Needed pollinators must be introduced and maintained
 Biological controls that are naturally occurring outside
the tunnel will be restricted from entering
 Not all mechanical controls are effective
 Ultrasonic
and electromagnetic devices
 Bug zappers
 Insect traps (yellow sticky cards)
Control Techniques: Chemical
 Use of pesticides, naturally occurring or synthetic
 Adversely
affect unwanted insects, weeds or plant
 Affect plant growth
 Repel insects from an area
 Judicious use in combination with other tactics
 Or,
if other tactics do not give desired level of control
 Thoughtfully chosen and properly timed application
 Least toxic alternatives
 Consider use of “soft” or “reduced risk” compounds
 Consider environmental consequences
Importance to Growers
 IPM practices must be compatible with objectives
 Practices must be:
 Economically
 Effective
 Understandable
 Practices
can be implemented in stages
Importance to Growers
 Approach should improve grower’s profitability and
reduce risk of crop loss
 Monitoring
used to determine economical timing
 Provides greater peace of mind
 High
tunnel production is large investment
 Proper field scouting for informed decisions
Importance to Environment
 All practices must be environmentally sound
 Benefits received from control vs. risks of that
control should be considered before practice is
 Reduces unnecessary pesticide applications
 Pesticides
are generally largest environmental concern
with pest management
 Fewer unwarranted pesticide applications such as
“calendar sprays”
High Tunnel Insect Control
 Major insect and mite pests of high tunnel crops
should be given consideration
 Avoid having lights on in evening or night near or
inside the high tunnel
 Security
lights or lights for convenience
 Lights attract a range of insects, particularly moths
 These insects may inadvertently cause crop damage
High Tunnel Insect Control
 Hornworms/Other Caterpillars of Tomato & Peppers
 Damage
usually occurs from midsummer to fall
 Eat
irregular holes in leaves and
may defoliate plants
 Camouflaged
– often difficult to see
 Fruitworms
 Feed
on green fruit
 Damage is deep watery cavities on stem end of fruit
 Inspect tomato plants for larvae on fruit and leaves
 Threshold in high tunnel is one caterpillar
 Can
be handpicked or use insecticide sprays
High Tunnel Insect Control
 Whiteflies
 Tiny,
resemble tiny white moths
 Disperse from plants when disturbed
 Most common on tomatoes and melons in late season
 Damage done when in immature (nymph) stage
 Suck
sap from plant leaves
 Spread viral diseases
 Inspect
plants for off-color or stunted plants
 Yellow sticky cards will monitor adults
 Spray with insecticide/insecticidal soap
High Tunnel Insect Control
 Aphids
 Migrate
into high tunnel from wild hosts
 Establish colonies on plants
 Soft-bodied, pear shaped small insects
 Usually
 Suck
on underside of leaves, may be found on stems
sap from plants
 Leaves
curl under, become deformed, weakens plants
 Can be vectors of plant diseases
 Scout
plants closest to openings
 Wide range of control options
High Tunnel Insect Control
 Spider Mites
 Tiny
(~.5mm long), live on undersides of plant leaves
 Puncture plant cells to feed on the sap
 Speckled
“bronzing” discoloration of leaves
 Reduced plant growth
 Possible early defoliation and death
 Thrive
in hot, dry weather and
are more likely from mid season
through fall
High Tunnel Insect Control
 Spider Mites (Continued)
 Inspect
leaf undersides for egg webs, cast skins and
all stages
 Control weeds and practice clean mowing around
tunnel to help prevent movement from outdoors
 Begin treatment when
symptoms appear
 Insecticidal
soap or other miticide
 Miticides do not kill eggs so repeat
application should be considered
High Tunnel Insect Control
 Thrips
 Small
(1/16 inch long) and elongated
 Found in flowers or on the undersides of leaves
 Damage to plants is caused by adults and nymphs
 Scrape
the surface of leaves with mouthparts
and feed on exuding sap
 Leaves will have small, silver streaks
 Plants look as though they have
been sandblasted
High Tunnel Insect Control
 Thrips (Continued)
 Early
detection is important
 Frequently inspect blossoms and leaf undersides
 Sticky traps can detect adult winged thrips
 Apply systemic, targeted insecticides at transplanting
 Effective
 For
in controlling for ~35 days on certain crops
control, spray contact
High Tunnel Insect Control
 Cucumber Beetles
 Same
beetles that that will attack
field-grown cucurbits
 Transmit
bacterial wilt
 Can damage high tunnel melons
 Overwintered
adults feeding on transplant leaves and
stems can kill small plants
 Surviving
 Frequently
 Reduces
plants may be infected with bacterial wilt
feed on the fruit surface
aesthetic appeal
 Creates openings for sap beetles and disease organisms
High Tunnel Insect Control
 Cucumber Beetles (Continued)
 Can
be excluded from transplants by
using row covers in the high tunnel
 Systemic insecticides applied at transplanting will
provide up to 35 days of control
 Long
enough to reduce bacterial wilt and infection
 Foliar
insecticides provide further control through
growing season
 Avoid
 No
insecticides that may be toxic to pollinating insects
effective biological control techniques
High Tunnel Plant Disease Control
 High tunnels can reduce disease impact by:
 Elevating
soil temperatures slightly
 Enough
to prevent common cool weather damping-off
and root rots
 Keeping
foliage dry
 Preventing
establishment of most foliar diseases
 Powdery Mildew can germinate
 Absence
of free water
 Can be even more serious than in a field-grown crop
High Tunnel Plant Disease Control
 Disease management should include the following
 Use
plastic mulch combined with trickle irrigation
 Keeps
foliage dry, reduce splash of soil-borne pathogens
 Maintain
humidity to remove excess moisture
 Provides
conditions conducive to certain diseases
 Use ventilation and follow plant-spacing guidelines
 Use
disease-resistant varieties when possible
 Always
start with disease-free seed and transplants
High Tunnel Plant Disease Control
 Disease management should include the following
 Provide
optimal growing conditions
 Proper
irrigation, fertilization, staking, pruning, etc.
 Increase plant health and vigor
 Practice
sanitation to remove and destroy infected
plants as they are found
 Pick
produce frequently, cleanly and completely
 Remove all over-ripe and damaged produce
 Remove all plant residues at the end of the season
 Practice
crop rotation
High Tunnel Plant Disease Control
 Powdery Mildew
 Major
problem for all high tunnel crops
 Environmental conditions in tunnel favor development
 Produces white, powdery colonies
 On
leaves, petioles, and stems of infected plants
 Usually
appears on lower leaves
 Gradually
 Plants
 Fruit
spreads through the canopy
become weakened from leaf loss
size can be significantly reduced
High Tunnel Plant Disease Control
 Powdery Mildew (Continued)
 Choose
resistant cultivars when possible
 Inspect plants regularly, starting at fruit set
 Many effective fungicides are labeled for control
 Includes
several synthetic fungicides and organic
products, such as mineral oils & potassium bicarbonate
 Alternate synthetic fungicides to prevent the
development of resistance

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