Pest Management Planningfor Organic Vegetable Production
Geoff Zehnder, CoordinatorIPM & Sustainable Agriculture Programs
Clemson [email protected]
My Background• Academics
– M.S. in IPM; Ph.D. in Entomology
• Work Experience– VA Tech: research on
potato ,tomato IPM– Auburn: research on
insect-plant interactions (induced resistance)
– Clemson: Extension training; grad student research
Outline• Principles of organic pest
management• Approaches to pest
management planning• Examples
• General preventative practices
• Targeted practices • Pest management at the
Clemson Student Organic Farm
Landmark Article that Proposed IPM Concept(IPM is the Foundation of Organic Pest Management)
• Recognized that toxic pesticides disrupt the agro-ecosystem– Need to conserve
beneficial insects• IPM
– Integrate multiple strategies
– Insecticides only when necessary based on pest damage thresholds
Authors: Vern Stern, Ray Smith, Robert van den Bosch, and Ken Hagen
Organic Pest Management(Certified Organic Production)
Foundation is in IPM, but: • Preventative pest management practices
must be used (long-term planning)
• Use of pesticides is limited to those that are produced from natural sources, not synthetic chemicals
• Approved pesticides are to be used only if preventative tactics fail
Principles of IPM in Organic Systems
• Not based on input substitution
• View cropping system as part of larger ecosystem– Try to achieve natural
ecosystem balance for pest regulation
– Take advantage of nature’s services
• Integrate control strategies in a compatible manner
Flowering strips in celery production: Tanimura & Antle
Growers, California
National Organic ProgramPest Management Guidelines
• No synthetic pesticides• No GMOs• Preventative pest
management plan• If necessary, use of
approved biological or mineral based products
• Buffer between organic and conventional fields
National Organic Programhttp://www.ams.usda.gov/nop
One way to think about transitioning from conventional to
organic IPMLow Level IPMScouting, use of thresholds, timed pesticide applications
Medium Level IPM (multi-tactic approaches)Begin to manipulate habitat, augment biodiversity, crop rotations, resistant varieties
Biointensive IPM • Advance planning to avoid/prevent pests• Emphasis on:
• Habitat to maintain natural enemies year-round• Cultural practices to make crops less suitable for pests
Three Levels of Pest ManagementLevel A (Cultural Practices and Habitat Diversity)The first line of defense in managing weed, insect, and disease pests is a systems-based approach. It is based on the fact that a well-designed and healthy organic system will naturally have fewer pest problems. The system is designed to prevent pest and disease outbreaks.
Level B (Mechanical and physical methods, release of biological control agents)The second line of defense is utilized if the practices of level A are not sufficient to control the weed, insect, or disease problem. Level B generally includes mechanical and physical practices that are traditional in organics, as well as the use of nonsynthetic or natural materials.
Level C (OMRI approved pesticides as a last resort)The third line of defense is used if the level of pest control required is not achieved after A and B control options are applied. Level C practices include the use of inputs such as biologicals and botanicals to control pests.
From: P. Coleman. 2012. Guide for organic crop producers. NCAT.www. attra.ncat.org
Organic Pest Management PlanGeneral Preventative vs. Targeted Practices
• General Preventative Practices– Start with general
preventative practices that can be incorporated as part of the farm plan• Once in place, they will
help to prevent pests from becoming a problem
• Targeted Practices– Maintain a ‘toolbox’ of
more directed or targeted practices for specific pest problems• These can be used if
needed…– Based on knowledge of
key pests that could occur on specific crops, and on pest biology and behavior
FOUNDATION
Some General Preventative Practices(often have multiple functions)
Rolled cover crop before no-till planting of peppers at the Clemson SOF
Cover Cropping/Conservation Tillage
• Multiple functions– Soil quality and fertility
• Organic matter, plant available nutrients.
– Pest Management• Healthy soil = healthy plants
better able to tolerate pests.• Enhances diversity of soil
microbes and arthropods.– Pest and disease
suppression• Flowering cover crops
attract natural enemies.• Weed control.
Melon-Virus ExperimentsCover crop makes plants less attractive to aphids and reduced incidence of watermelon mosaic virus (WMV)
• Annual rye planted between rows in late fall
• Virus incidence lower in cover crop treatments
• Reflective mulch also reduced virus incidence
2003 20040
50
100
CoverNo Cover
% Plants Infected with WMV
Soil Quality ManagementDoes it affect above-ground pest damage?
Research on European Corn BorerLarry Phelan, Ohio State University
• Compared egg-laying on plants grown in soil from organic vs conventional farms
• Significantly more ECB eggs laid on plants in conventional soil
• Mineral Balance Hypothesis: – Organic, microbe-rich soils
release plant nutrients more evenly over time
– More even plant growth rate; less suitable for insect pest development
Microbial Inoculants• Products are proprietary
– Beneficial bacteria, fungi, strain mixtures
• Applied to seedlings in greenhouse and at transplanting in the field
• Benefits – Plant growth promotion – Yield increase– May stimulate plant
defense against disease– Not a silver bullet control
Plant growth-promoting rhizobacteria (PGPR): Experiments with cucumber beetle and bacterial wilt of cucurbits
Rotation with Biofumigation Crops
• Brassica “break crops” (mustards, rape, etc.)– Breaks pest/disease
lifecycle• Direct effects: biocidal toxicity
– Glucosinolates converted to isothiocyanates
– Toxic to pathogens, weed seeds, soil insects
• Indirect effects: – Changes in soil microbial
community
Adding Plant Diversity (Farmscaping)
• Provides food and shelter for natural enemies (predators and parasites) and pollinators– Favorable microclimate– Supply of nectar and pollen– Habitat– Alternative hosts or prey– Research
• Level of bio-control related to seasonal availability of insectary plants and proximity to crops
• Establish habitat on at least 1-5% of production area
www.xerces.org
Other Important Cultural Practices
• Crop rotation• Inter-cropping (mixed
plantings)• Sanitation• Fertility and water
management
Resources listed in the Appendix
More Targeted Practices
Using Multiple Stategies Organic Control “Toolbox” for Cucumber Beetle
• Habitat for natural enemies • Grow cucurbit varieties less attractive
to beetles• Long distance crop rotation• Transplant vs direct seeding• Eliminate crop residues• Manipulate planting date (may miss
peak markets)• Row covers (may interfere with
weeding)• Mulch (may exacerbate other pests)• Trellis plants (labor)• Trap crops, baits and sticky traps
(labor, cost)• Approved materials
– Neem, Beauveria bassiana, kaolin clay, pyrethrin, spinosad, microbial inoculants
Disease Resistant Varieties
Cornell Vegetable MD Online: http://vegetablemdonline.ppath.cornell.edu/
Vegetable Grafting
www.vegetablegrafting.org
Research, list-serve, training calendar, rootstock lists
Using Knowledge of Insect Behavior
Pickleworm
• Overwinter in Florida
• Don’t arrive in SC until early July
Plant early before moths arrive
Diamondback Moth
• Yellow rocket highly attractive to moths for oviposition, but larvae don’t survive
Use yellow rocket as a trap crop
Colorado PB
• Adults OW in soil• Emerge in spring
when temps are cool
• Find host plants by walking
Mulch interferes with host location
Pest Monitoring/Sampling Plan
• Monitoring Crops– frequency– procedure– pest ID– recordkeeping– action thresholds
• Have approved materials on hand if needed
Use of Approved Pesticides
• Only if other strategies fail– “Input Substitution” not
allowed• Degrade quickly; low
potency; short residual activity
ON THE TROT: Stuart, a 22-year-old former trotter, tows the organic sprayer between the vines at
Seresin winery in New Zealand
Specialized Application
Dropleg application of Bt for control of caterpillars in leek.
Air-assist backpack sprayer
Chelsi Crawford
Shawn Jadrnicek Kelly Gilkerson
Amy Nichols
Pest Management at the Clemson Student Organic Farm
Student Organic FarmStandard Operating Procedures (SOPs)
PESTICIDES
Bt (Dipel, Javelin etc.): Used to control caterpillar damage mainly on Brassica’s but also on summer squash. Apply when butterflies are seen visiting Brassica’s or when white eggs that look like very small grains of rice are found on Brassica leaves or when Brassica leaves are damaged by caterpillars. Apply to summer squash when pickle worms are evident or squash vine borer damage is expected. Re-apply after rain events. Add a squirt of soap as a surfactant. Read and follow label directions before applying.
Copper Hydroxide (Champion): Use on tomatoes if risk of disease is high based on forecasting models ((i.e. TOMCAST, BLIGHTCAST). Use sparingly to prevent copper from building up to toxic levels in the soil. Read and follow label directions before using. Warning: eye irritant.
Daily Farm Log• All farm activities entered
by hand at end of the day– Workers trained to ID
pests/diseases– Pest/disease/weed
conditions are noted daily– Treatment thresholds
based on experience– Pest control actions
including any inputs are recorded
• Log provided during annual organic audit
FarmscapingPonds and Flowering Plants
Successive plantings of cut flowers, sunflower and buckwheatPerennial flowering plants; elderberry, blackberry, J. artichoke, etc
Flea Beetles• Early season
Brassicas– Surround™ before
transplanting in field
May use Pyganic™ for insects on
outside transplants
Ratooning Eggplant
• Mow first planting at 8-10” height
• Surround™ + Pyganic™ if needed to control flea beetles in late summer
• Plants produce fruit 5-6 weeks after mowing
Fruit damage from flea beetle feeding inside flowers
Colorado Potato Beetle
• Hand pick 2-3x per week• Crop rotation; straw mulch• Flame weeding at plant emergence• 1 x Spinosad (Entrust™) if larvae
escape
Planting Windows• Squash (cucurbits)
– Don’t plant late• But, plants grow more
slowly when cool; more susceptible to pests
– Early plantings avoid pickleworm, squash bug and diseases
– At $2/lb you can harvest for a few weeks and terminate crop
Reducing Disease Risk• Vegetable Crops Handbook
– Resistant varieties– Optimal planting date for
vigorous growth
• Crop rotation• Grow lots of storage
vegetables to sell later (winter squash, onions, potatoes, etc)
• Experiment with microbial inoculants
• Grading for drainage– Place drive/walk rows on ridge– Crop rows at 0.5° slope for
drainage– Drainage furrow at end of
rows• Soil can be used to fill
low spots
Yellow Nutsedge• Grows well in wet,
poorly drained soil – Caulk punched holes
in drip tape• Incorporate sweet
potatoes in rotation
Flaming Weeds• Carrots:
– Place clear plastic cover over a section of row
– Flame when carrots emerge under cover
• Stale seed bed; prep beds every 2 weeks– Direct seeded; flame
before plants emerge– Transplants; flame
before transplanting
Cultivating Equipment
Wings reform furrows
Sweeps/tines remove weeds
Spider wheels throw soil against transplants to bury weeds
Organic No-tillDavid Robb (grad student)
Average yield/unit of effort
Weeding and Irrigation– Level (kg/min)– No-till squash A 2.1– Tilled squash B 0.5– Levels not connected by same letter are significantly different.
– Level (kg/min)– No-till tomato A 0.9 – Tilled tomato B 0.1– Levels not connected by same letter are significantly different.
Example: for every minute of maintenance done per row of no-till squash, there was an average yield of 2.1kg.
CROP TOTAL MAINTENANCE (hrs)
TOTAL IRRIGATION
APPLIED (gallons)
NO-TILL SQUASH
2.2 1,150.4
TILLED SQUASH
9.4 1,725.5
NO-TILL TOMATO
2.2 1,604.8
TILLED TOMATO
10.3 2,362.3
Questions?
Articles on Sanitation Methods for Pest Management
University of Florida IFAS: Cultural Controls: Field Sanitation http://ipm.ifas.ufl.edu/pdfs/Field_Sanitation.pdf
Michigan State University: Sanitation is critical to prevent diseases Part 2: field sanitation
http://msue.anr.msu.edu/news/sanitation_is_critical_to_prevent_plant_diseases_part_2_field_sanitation
Purdue University: Managing Pests in Home Fruit Plantingshttps://www.extension.purdue.edu/extmedia/id/id-146-w.pdf
University of Kentucky: Fruit, Orchard and Vineyard Sanitation Fact Sheet http://articles.extension.org/pages/70066/fruit-orchard-and-vineyard-sanitation-fact-sheet
APPENDIX
Articles on Crop Rotation
SARE: Crop Rotation on Organic Farms (case histories from NE farms but also applicable to other regions)http://www.sare.org/Learning-Center/Books/Crop-Rotation-on-Organic-Farms SARE: Managing Plant Diseases with Crop Rotationhttp://www.sare.org/Learning-Center/Books/Crop-Rotation-on-Organic-Farms/Text-Version/Physical-and-Biological-Processes-In-Crop-Production/Managing-Plant-Diseases-With-Crop-Rotation#Table3.5 SARE: Management of Insect Pests with Crop Rotationhttp://www.sare.org/Learning-Center/Books/Crop-Rotation-on-Organic-Farms/Text-Version/Physical-and-Biological-Processes-In-Crop-Production/Management-of-Insect-Pests-with-Crop-Rotation-and-Field-Layout Center for Environmental Farming Systems: Crop Rotations on Organic Farmshttp://www.cefs.ncsu.edu/%5C/resources/organicproductionguide/croprotationsfinaljan09.pdf
APPENDIX
Articles on Over-fertilization and Insect Pests
SARE: Impact of Fertilizers on Insect Pestshttp://www.sare.org/Learning-Center/Books/Manage-Insects-on-Your-Farm/Text-Version/Managing-Soils-to-Minimize-Crop-Pests/Impacts-of-Fertilizers-on-Insect-Pests M. Altieri: Soil Fertility Management and Insect Pestshttp://www.agroeco.org/doc/soil-pestmgmt.pdf California Agriculture: Excess N raises nectarine susceptibility to disease and insect pestshttp://ucanr.edu/repositoryfiles/ca4904p13-69972.pdf
APPENDIX