Audience Question. Nuts and Bolts of Organic Land Management. What does the term organic gardening mean to you? Preview of Presentation

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1 Nuts and Bolts of Organic Land Management Audience Question What does the term organic gardening mean to you? Weston Miller Master Gardener 2011 Preview of Presentation Organics explained Organic management practices Soil building Conservation Biological Control Organic techniques and products Techniques Products Fertilizers, pest control, sterilization Interest in Organic Gardening 5% of America s 90 million households use exclusively organic management An additional 31% are hybrid gardeners Trend expected to double in coming years Organic Movement Response to increasing input of synthetic chemical pesticides and fertilizers on farms, gardens, and landscapes General public thinks: organic = pesticide free National Gardening Association. (2005). Environmental Lawn and Garden Survey. South Burlington: National Gardening Association. Retrieved May 12, 2008 at 1

2 Confusion!!! Organic is not necessarily sustainable Organic Movement Connected to environmental movement Rachel Carson Silent Spring Organic Industry Trickle-down effect from organic foods industry to gardening The Word Organic in Context Organic chemistry- contains carbon The Word Organic in Context Organic matter- residue from plant and animals as part of compost, manure, cover crops, mulch, and fertilizers made of natural materials The Word Organic in Context Organic agriculture and foods Defined by United States Department of Agriculture (USDA) 2

3 Organic Agriculture is Federally Defined USDA National Organic Standards Board 1995: Organic agriculture is an ecological production management system that promotes and enhances biodiversity, biological cycles and soil biological activity. It is based on minimal use of off-farm inputs and on management practices that restore, maintain and enhance ecological harmony. Agricultural practices that: Mimic natural ecosystems Maintain/replenish soil fertility Practically Speaking No use of synthetic chemical pesticides and fertilizers Use natural products: Derived from mineral, plant, animal Organic Food Labeling Grown and handled according to standards Minimally processed Maintain the integrity of the food No artificial preservatives No irradiation No GMO Services include: Certification Education Research Resources Oregon Tilth What s a gardener to do? No certification required If you want to meet NOP standards: USDA National List of Allowed and Prohibited products Organic Materials Review Institute (OMRI) Northwest Center for Alternatives to Pesticides (NCAP) 3

4 Organic does not mean Pesticide free or chemical free simply means products are derived from natural sources Decisions, Decisions, Decisions Organic Gardening Products Soil amendments / fertilizers Herbicides Pesticides Disease Control Based on Ecological Principles Ecosystem Structure Ecology Study of the environment and the relations of organisms to each other and their surrounding Biotic Community Consumers Physical Environment Energy Nutrients Ecosystem Collection of interacting organisms and abiotic components in the physical environment Primary Producers Scavengers Decomposers Climate Ecosystem Services- UN It s not Rocket Science 4

5 Components of Ecosystem Landscape Ecology Pest Complex Natural Enemies Disease Complex It s Life! Land Soil Plant Diversity Management Abiotic Factors Land Soil Nematodes Micro/ Macro Invertebrates Nutrients Microbial Flora Organic Matter Courtesy of Gail Langellotto Even though it s complicated People have been successfully growing plants without synthesized chemical fertilizers and pesticides for 1000s of years through: Through: The farm/garden does not end at edge of the property Keen observation Local cycling of nutrients Major investment of time Use of animals 5

6 Agroecosystem Organization Principles of Ecological Land Management Regional Ecosystem Farm Ecosystem Field Community Crop Population Crop Plant Manage Ecological Relationships Reestablish ecological relationships Enhance beneficial biota Minimize disturbance Use nutrient recyclers- compost, worms, fowl, goats, etc. Manage pests, diseases, and weeds instead of controlling them. Re-establish Ecology Enhance beneficial biota Minimize disturbance 6

7 Harness nutrient recyclers compost, worms, fowl, goats, etc. Trench compost and ducks Worm Food! Manage pests diseases weeds instead of controlling them. Manage Pests 7

8 Organic Practices: 1. Build Healthy Soil for Healthy Plants 2. Biorational Pest Management Soil Building- Compost Cover crops Digging techniques Organic fertilizers Tilth the state of aggregation of a soil especially in relation to its suitability for crop growth Soil Components Our job as gardeners: Maintain and enhance tilth in soil through addition of composted organic material (balanced) and regimented care (CA Fertilizer Association) Soil Building Goal is to provide food for soil biology Soil Fungi Soil biology: creates favorable structure makes nutrients available to plants Mineral from parent soil Organic matter / amendments 8

9 Soil Food Web Soil Bacteria Feed plants by feeding the soil Feed plants by feeding the soil Components of Soil Organic Matter Soil Structure is Improved by Soil Life Aggregation from biological activity influences: Soil porosity (spaces) & permeability (water entry) Water movement & holding capacity Improves root growth Improves environment for beneficial organisms Role of organic matter 9

10 Organic Matter Key to long term fertility Improves quality of most soils Breaks down to form humus (natural glue) Strengthens aggregates Improves water holding capacity Releases plant nutrients Provides food for beneficial organisms Soil Aggregate Soil aggregation is important for getting water into soil - permeability Adding organic matter Low C/N ratio, high nutrient value: raw manure, blood meal, feather meal, less contribution to organic matter, use sparingly, do not exceed N and P requirements Medium C/N ratio, lower nutrient value: compost, leaf mulch and cover crops, add in large quantities High C/N ratio, can immobilize N: straw, bark & sawdust Building Soils for Better Crops. Chapter 4. Compost Organic matter Some nutrients Nutrient quality varies widely Hard to make good home-made compost without lots of work 2 / crop season Nitrogen sources Previous compost applications Crop residues Cover crops legumes fix nitrogen, grasses reduce losses to leaching Soil organic matter (10-30lbs N/acre for each 1% organic matter) Supplemental fertilizers ie. blood, corn, fish, alfalfa meal 10

11 Reduce Nitrogen losses Rain and over-irrigation = leaching Cultivation Evaporation incorporate amendments Minimize leaks in the nitrogen bucket! Crop removal incorporate residues Or compost and apply later Organic Fertilizers Cumulative available N from an organic source Material % N % P % K Cotton seed meal Blood meal Alfalfa Bat guano Fish meal Fish emulsion Bone meal Rock phosphate Greensand Kelp meal Year = available N + Sustainable Gardening, Pg Time Lag Nutrients from most organic sources are not available immediately. Either: March April May June Plan ahead and time planting Use water soluble N at planting Organic Fertilizer Mixtures Steve Solomon trace minerals Use up to 4# / 100 square feet 4 parts seed meal ½ part lime (agricultural and dolomite) ½ part rock phosphate or bone meal ½ part kelp meal 11

12 Cover Crop Benefits Reduce erosion Protect soil structure Fix N and improve nutrient availability Supply N without increasing soil P Reduce nitrate leaching Increase soil organic matter Improve mycorrhizal winter survival Reduce weed pressure Provide nectar & pollen for beneficial insects Selecting cover crops To reduce, leaching use grasses To increase, organic matter use grasses and buckwheat To reduce weeds, plant high over-seed and plant early Selecting cover crops Nitrogen fixation To increase N use legumes To feed beneficial insects incorporate after flowering To combine benefits use mixtures of cover crops Atmosphere contains 78% N 2 but it is unavailable to plants Rhizobia spp. colonize legume roots and convert N to NH 3 They exchange NH 3 for carbohydrates Make Sure to Inoculate Nitrogen fixation specifics N-fixation is highest when: ph is near neutral, N is low, other nutrients are plentiful. Rhizobia must be fresh inoculate just before seeding with sugar water Be sure to use Rhizobia that are compatible with your crop clover group, pea & vetch group, etc. Incorporate at 30% flowering for most N 12

13 Contribution of Cover Crops (N - P - K) alfalfa ( ) crimson clover ( ) Austrian field peas (3-0 -1) annual rye (1-0-1). Winter Cover Crop Choices Annual rye Common vetch Austrian field peas 3-way mixture n Penhalagon, OSU Extension Crimson clover Over-seeded clover April 5 th, 2007 Over-seeded red clover planted late June/early July just before last cultivation and canopy closed. Photo Oct 17 th, 2006 Winter Cover Crop Timing Guideline End of September at latest Late August/ Early Sept is best Winter Cover Crop Practicality in Garden Setting? 13

14 Extreme measures to deal with winter cover crops Cut down with scythe or weed whacker Chop in as best you can Recommended for Gardens Add slow-release fertilizer Cover with black plastic for 4-6 weeks Winter Veggie Beds Thick layer of leaves Put in paths in spring Summer Cover Crops: Daikon, Buckwheat Coffee sacks Fallow = weeds Faba Beans: Grow as vegetable Phacelia 14

15 Sudhan grass Sept 12 th, 2006 Deep Cultivation For garden Double digging Broad fork Raised beds For landscapes: mix compost 18 deep Hand digging Mechanical digger Organic Pest and Disease Control Photo: Lindsay DuToit Biorational Pest Management- Prevention Manage own expectations Attract beneficial organisms Understand life cycle of pests/disease Cultural/physical techniques for pest management Judicious use of least-toxic pesticides An ounce of prevention is worth a pound of cure (Benjamin Franklin, ). Healthy landscapes prevent pest outbreaks Healthy plants resist pest damage 15

16 Audience Question What can you do to prevent pest problems from developing in vegetable gardens and landscapes? Particularly important for organic methods. Prevention Take care of soil Drainage Right plant, right place Choose adapted crops and varieties Resistant varieties Prevention Avoid over watering or under watering. Plan a watering schedule Irrigate in the morning Irrigate soil, not plants Provide air flow. Prevention Prevention Rotate crops Maintain/improve soil quality: Use cover crops and/or compost. Don t over cultivate Don t cultivate when it s wet. Prevention Provide food, shelter and habitat for beneficial organisms: Hedgerows, Beetle banks, Insectary plants Year-round flowers 16

17 Diverse Plant Species and Architecture Provide for insect needs: Flowers Nectar for energy Pollen for nutrients Water bath Refugia for egg laying Conservation Biological Control Increases the abundance of natural enemies where the habitat has been manipulated (Langellotto and Denno 2004) Spatial scale of conservation biological control area influences success (Langellotto and Rosenheim) Conservation Biological Control Few studies have been conducted in garden Exception: Shrewsbury and Raupp (2006). Do topdown or bottom up forces determine Stephanities pyriodes in urban landscapes? Beetle Banks Hedgerow Two Dimensional System Three Dimensional System Field Margin Conservation Biological Control Reduce Disturbance pesticide use, raking, mowing, etc. Provide shelter and water Nectar and pollen for insects Tolerate parasitized insect hosts Spiders Parasitized Cabbage Moth Larvae Pollinators at Risk Both European Honey Bee and Native Pollinators populations down Possible causes: Habitat loss Loss of floral diversity Invasive plants Widespread use of pesticides Climate change Pests and disease National Research Council

18 Pollinators Bumblebee European Honey Bee Orchard Mason Bees Clackamas County Master Gardeners Farmscaping for Beneficials Project Sunflower, buckwheat and wild Cruciferae insectary plantings Calendula, orache, Alyssum insectary strips, among vegetable crop rows Beetle bank Photos from IPPC Farmscaping for Beneficials Project Beetle Bank Native bunch grasses provide refuge Put 1 above existing grade Carabid beetle Rove beetle s/insect/key_predators.htm Adults are dark or metallic Larvae are grublike with large mouthparts. Feed on soil organisms. Active at night. Ground beetles Scaphinotus marginatus larvae and adult (Ken Gray image collection) 18

19 Companion planting: establishment of two or more plant species in close proximity so that some benefit is derived Trap cropping Biochemical pest suppression (rye) Spatial interactions (Corn n squash) Beneficial habitats Security through diversity mix cultivars Companions Intercropping with insectary plants Attracting Beneficials (Table 3 pg. 448, 450) Lettuce Cilantro/coriander Apiaceae- parsley Asteraceae- calendula Brassicaceae- arugula Dispacaceae- Teasel, blue buttons Fabaceae- fava bean, clovers Hydrophyllaceae- phacalia Polygonaceae- buckwheat Buckwheat Fiddleneck (Phacelia) 19

20 Some Guidelines NRCS- Technical Notes Continuous bloom Big, close, interconnected patches Diversity (flower type, color, architecture, annuals, perennials) Native and traditional varieties sentations/farm_insectary_plant_manu al_draft2_pressqual1.pdf Plants for Pollinators in Oregon 8 or more species grouped at site abundance and diversity 3 plants during each blooming period (early spring, spring, summer) 1 native bunch grass ftp://ftpfc.sc.egov.usda.gov/or/tec hnical_notes/plant%20mat erials/pmc13.pdf Annual Garden Plant Flowering Sequence Early spring flowering Mustards (arugula), fava beans, calendula Spring flowering Basil, coriander, squash Summer flowering dill, parsley, sunflower Perennial Plant Flowering Sequence Early spring flowering Seaside daisy, allium, sedum, lupine*, strawberries Spring flowering Agastache, lavender, rosemary, rue*, alyssum*, oregano, yarrow Summer flowering Statice*, parsley, yarrow*, feverfew* NRCS- Plants for Pollinators NRCS- Plants for Pollinators Field Guide to Natural Enemies Lady beetles Larvae and adults eat aphids, mealy bugs, mites and insect eggs

21 Yum! Caterpillar for lunch! Lady beetle larva Lacewings Larvae eat aphids, thrips and mealy bugs Green lacewing eggs Adults eat pollen and nectar Eggs on stalks Green lacewing larva dining on a caterpillar Purchasing and Releasing Beneficial Insects Hover flies (Syrphid) Larvae eat aphids and thrips Adults eat pollen and nectar Mimic wasp appearance, but they hover in flight Eggs are laid in aphid colonies, larvae feed on aphids. 21

22 Praying mantis Assassin bug Spiders Parasitoids Aphid Parasitoid Wasps Adults mostly <1/8 long Lay eggs in aphid host Adults feed on aphid honeydew, nectar and pollen Larvae develop inside aphid and emerge as adults Monitor by looking for aphid mummies More species specific than predators Parasitic wasp laying eggs in aphid 22

23 Aphid mummies Tachinid fly Tachinid fly and elm leaf beetle larvae Vertebrates Violet-green swallow Song Birds Common Garter Snake Toad David Rosen Pacific Chorus Frog David Rosen All bat species in Oregon are insectivores 23

24 Many insects in the soil are beneficial Springtail Oribatid mites Organic Herbicides Organic Weed Control Acetic acid (vinegar-based) Clove/citric acid based Herbicidal Soap Contact Non-selective Do not translocate OK for annuals Perennials- hmmm Organic Pest and Disease Control Products 1.Pest control 2.Disease control 3.Sterilization Organic Products USDA National List of Allowed and Prohibited Substances Organic Materials Review Institute (OMRI) Washing State Department of Agriculture (WSDA) 24

25 Label is the law With All Products Identify plant and pest and confirm on label for allowed uses of product Read and follow the directions! Wear proper eye protection, mask, clothing, gloves, etc. Organic Pesticides Azadirachtin- Neem Bt- biological Beauveria bassiana- biological Horticultural oils Insecticidal soap Iron phosphate- slugs Kaolin clay Lime Sulfur Pyrethrins Rotenone Spinosad Sulfur Biological Products Beneficial microorganisms Bacillus thuringiensis or Bt B.t. israelensis and mosquitos Dunk B.t. kurstaki and caterpillars 25

26 B.t. israelensis and fungus gnats B.t. san diego and elm leaf beetle Beauvaria bassiana Spinosad Organic Chemical Methods: Botanical Insecticides Botanical insecticide: Neem Derived from botanical sources Biodegrade rapidly Widely varying levels of toxicity From seeds of the neem tree Broad spectrum against many pests Must be ingested to be toxic Low mammalian toxicity May require repeat applications 26

27 Insecticidal Soap Contact insecticide smothers and desiccates insect Use against soft-bodied insects like aphids, thrips, whitefly, and mites Low mammalian toxicity Requires excellent coverage, repeat applications Biodegrades rapidly Effective only until it dries You cannot recommend homemade solutions! Horticultural Oil Derived from petroleum, vegetable or fish oil Smothers insects and mites Works best on soft-bodied insects Low mammalian toxicity Avoid hottest part of day Avoid drought-stressed plants Use commercial products rather than homemade Use dust mask with dust product Broad spectrum miticide and fungicide Low mammalian toxicity Do not use within two weeks of an oil spray Some plants sensitive to sulfur Sulfur Organic Fungicides Propagation Sterilization Horticultural oils inc. neem Copper based Sulfur Serenade (Bacillus subtilus) Baking soda (K) 10% Bleach solution Isopropyl alcohol H2O2 This is a peach tree grafted with two curl resistant cultivars. Cultivar 'Q 1-8' on the left and the cultivar 'Mary Jane' (with lots of curl) on the right. Materials Allowed for Organic Disease Management- PNW Disease 27

28 Review Organics defined An ecological approach Soil building Pest management Organic gardening techniques and products 28