Transcript Lecture #3 Sections 10.4 & 10.5

Lecture #3 Sections 10.4 & 10.5
Alternatives to Current Pesticide Uses
& Reducing Pesticide exposure
Alternatives to Pesticide Use
• Behavioral Changes
– Crop Rotation
– Mechanical Cultivation
– Flooding Fields
– Habitat Diversification
– Growing in Pest-Free Zones
– Adjusting Planting Times
– Plant Mixed Polycultures
– Tillage at the Right Time
Biological Controls
• Predators or pathogens
• Insects that eat weeds
• Plants like the neem tree
that make their own
pesticides
• Bioengineering
• Release of sterile male
insects
• Hormones that disrupt
development or attract
insects to traps
Integrated Pest Management
• Flexible, ecologically-based strategy that uses a
combination of techniques applied at specific times
aimed at specific pests
– Tries to minimize use of chemical controls and
avoids broad spectrum controls
– Uses preventative practices to encourage
beneficial organisms and enhance plant defenses
– Employs economic thresholds to determine the
point at which potential economic damage
justifies pest control expenditures
Integrated Pest Management
– Time, type and method of application are critical
– Trap crops - small areas planted before the main
crop. These plants mature first and attract the
insects, and the trap crop is then sprayed heavily
to destroy them. Crop is cut down and not sold.
• IPM is being used successfully all over the world.
Cuts pesticide use while maintaining yield.
– But must be careful that introduced organisms do
not become pests themselves
Reducing Pesticide Exposure
• Less than 10% of active pesticide ingredients have
been subjected to a full battery of chronic healtheffect tests.
– Of the 321 pesticides screened, EPA reports 146
are probable human carcinogens.
• Since 1972, only 40 pesticides have been
banned.
Regulating Pesticides
• Environmental Protection Agency (EPA), Food and
Drug Administration (FDA) and Department of
Agriculture (USDA) all share federal responsibility for
regulating pesticides used in food production in the
U.S.
– EPA regulates sale and use, and sets tolerance
levels.
– FDA and USDA enforce pesticide use and
tolerance levels set by EPA.
Regulating Pesticides
• In 1996, Congress passed Food Quality Protection Act
requiring the EPA to set aggregate exposure limits and
examine inert ingredients in pesticides.
• Based on the new rules, EPA banned use of methyl
parathion on all fruits and many vegetables and
prohibited use of Dursban.
• Studies show children are more susceptible than adults
to toxic pesticides. Ban of CCA treated lumber
(chromated copper arsenate) used in play equipment and
decks.
Regulating Pesticides
• 38% of fruits and 12% of
U.S. vegetables are
imported. Less than 0.2%
is inspected for pesticides,
which are widely used in
developing nations.
Is Organic the Answer?
• Numerous studies have shown organic, sustainable
agriculture is more eco-friendly and leaves soil
healthier than intensive, chemical-based monoculture cropping.
– Currently, less than 1% of all American farmland is
organic but market is growing.
– Organic food must be produced without the use of
hormones, antibiotics, pesticides, synthetic
fertilizers or genetic modification.
– Animals must be raised on organic feed, given
access to the outdoors, given no steroids or
growth hormones and given antibiotics only to
treat disease.
Is Organic the Answer?
• Critics are disappointed by limited scope of the
definition of organic. They hope to include:
– Growing food in harmony with nature
– Food distribution based on co-ops, farmer’s
markets, and local production
– Food should be simple, wholesome, nutritious. At
present, processed ingredients are allowed in
organic food.
• Some doubt whether organic growers can produce
enough to feed everyone.