Starting into Organic Production

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Great Lakes Fruit, Vegetable & Farm Market EXPO December 10-12, 2013 DeVos Place Convention Center, Grand Rapids, MI Starting into Organic Production Thursday morning 9:00 am Where: Gallery Overlook (upper level) Room A & B MI Recertification credits: 1 (COMM CORE, PRIV CORE) CCA Credits: SW(1.0) CM(1.0) Moderator: Vicki Morrone, Outreach Specialist for Organic Fruit and Vegetable Growers, MSU 9:00 am Organic Certification vs. Organic Production Vicki Morrone, Outreach Specialist for Organic Fruit and Vegetable Growers, MSU 9:20 am Establishing a Soil Health Program for Your Farm Joe Scrimger, Bio-Systems, Marlette, MI 10:00 am Cover Crops and Other Tools for Weed Management James DeDecker, Extension Educator, MSU Extension, Rogers City, MI 10:30 am Planning Your Varieties to Match Your Market Demand Anthony Cinzori, Cinzori Family Farms, Ceresco, MI 11:00 am Speaker Panel Question & Answer 11:30 am Session Ends

11/25/2013 7876 S. Van Dyke Road Marlette, MI 48453 Chemical Control Focus on Volume Production (989) 635-2864 Change Soil Culture bio-systems@centurytel.net 2 Glyphosate- Manganese Deficiency Manganese Deficiency Reduced uptake Fe, K & Mn Reduced N Fixation Drought stress Biological Control Focus on Quality Production Cover Crop Green Manure Crop Rotation Timely Cultivation Quality Compost & Manure Balanced Nutrients Timely Application Trace Minerals Focus on Beneficial Insects Create The Environment If You Build it they WILL COME Bacteria yields Nitrogen Fungal yields Phosphate Mycorrhizae yields moisture and phosphate efficiency Nematodes are soil quality indicators 4 Nematodes, Mycorrhizal Soil Basis for our Nations Health Minerals & Biology working together Most nematodes in the soil are not plant parasites. Beneficial nematodes help control disease and cycle nutrients. Credit: Elaine R. Ingham Improve Soil Structure & stability Decrease erosion & topsoil loss Enhances nutrient retention Credit: http://www.ars.usda.gov/sp2userfiles/person/49 47/Presentations/ScagelMycorrhizaeOhioCents0 6.pdf A predatory nematode consumes a smaller nematode. Credit: Kathy Merrifield, Oregon State University, Corvallis 1

(NUTRIENTS AND RECOMMENDATIONS ARE EXPRESS IN #/A UNLESS OTHERWISE NOTED.) 11/25/2013 NITROGEN CYCLE NUTRIENT CYCLE Need a deep rooting Legume in transition and in the beginning years of Organic Farming LEGUME NITROGEN Alfalfa 1 st Year 2 nd Year 3 rd Year 100+ 75 50 For the soil to be Biologically managed, you need: Adequate soil bacterial populations, which release: Nitrogen Calcium Other minerals CONVENTIONAL NITROGEN Purchase 120# to 180# of Elemental Nitrogen Organic Matter and Estimated Nitrogen Release BIO-SYSTEMS SOIL ANALYSIS REPORT FARM NAME: SAMPLE FARM DATE: 6/11/2008 CLIENT NAME: MR. SAMPLE FIELD: G-1 ACRES: PREV. CROP: VEGGIE CROP: VEGGIE FUTURE CROP: VEGGIE TEST DATE 6/11/2008 6/5/2008 BIOLOGICAL RECOMMENDATIONS AMOUNT Conventional Ag: Quantity ~vs~ Quality Pounds Per Acre Nitrogen *% Organic Matter Clay Loam Soil Sandy Loam Soil 0 0.3 30 55 0.4 0.7 40 65 0.8 1.2 50 75 1.3 1.7 60 85 1.8 2.2 70 95 2.3 2.7 80 105 2.8 3.2 90 115 3.3 3.7 100 125 3.8 4.2 110 135 4.3 4.7 120 145 4.8 5.2 130 155 5.3 5.7 140 165 5.8 6.2 150 175 6.3 6.7 160 185 6.8 7.2 170 195 7.3 7.7 180 205 7.8 8.2 190 215 70# Rule 3% OM => 100# Nitrogen Before Legumes Animal Manure Compost Green Manure or Cover Crops LAB A & L BIO-TEST APPLIED % O.M. 4.6 VERY GOOD E.N.R. No Nitrogen needed NITRATE 80+ HIGH AMMONIA 2 LOW AVAIL. P2O5 460+ VERY GOOD P1/P2O5 VERY GOOD 1310 No Phosphate needed P2/P205 1920 VERY GOOD Restrict all Phosphate sources SOLUBLE VERY HIGH No Potash needed K2O 480+ K2O TOO HIGH Restrict all Potash 695 sources MAGNESIUM 430 TOO HIGH No Magnesium needed SOLUBLE Ca LOW/MED 1000# High Calcium Lime 1400 Ca MEDIUM 750# Gypsum 2400 ph SOIL 6.7 6.2 GOOD/MED ph BUFFER 6.9 C.E.C. 9.7 GOOD Ok ENERGY 335 VERY GOOD Ok % BASE SAT. K 7.6 TOO HIGH Restrict Mg 18.4 TOO HIGH Gypsum will help lower Ca 61.6 MEDIUM Gypsum and High Calcium Lime H 12.3 TOO HIGH High Calcium Lime will lower S - ppm 18.0 LOW/MED Gypsum Zn - ppm 26.9 VERY HIGH Limit Mn - ppm 40.0 VERY GOOD Ok Fe - ppm 39.0 VERY GOOD Ok Cu - ppm 1.4 GOOD Ok B - ppm 0.8 MEDIUM 5# Borate-10% B This area tests too high in reserve phosphate and potash. Excess phosphate does not OVERVIEW: cause a nutritional problem but excess potash solubility does. Gypsum will help counter the effect of the high potash, but in the longer term you need to harvest all crop residues and add them to the compost pile to be put on another field until the potash level comes down. A 3-5% potash level is desired and you are at 7%, which is twice what your soil can handle. A base P1 level of phosphate at 750 pounds would (OVER) Excess Nitrogen yields Poor Cell Structure (i.e. Mushy Fruit) Excess Potash also leads to Weed Pressure & Fibrous Fruits High Levels of Nitrogen & Potash Represent Typical Conventional Ag Results 2

11/25/2013 13 Organic Soil Tends to be Lower in Nitrogen Lower in Potassium Conventional Soil Tends to be Higher in Nitrogen Higher in Potassium Organic soils use nitrogen more efficiently! Many Farmers Like to Follow Recipes Use a recipe made for your soil needs, and change it as your soils change If you don t change your recipe, you overfeed Over-application of Nitrogen will stimulate: Weeds Pests Disease Not changing your recipe will also decrease feed value Excess nitrate ends up in the feed! ORGANIC NITROGEN DO THE MATH CROP ROTATION 1 st Year 2 nd Year 3 rd Year 4 th Year Small Grain/Clover Clover Seed Green Beans Sweet Corn Nitrogen Clover- (Seed) 75# Manures- (4-4-2) Dried Poultry 1250# 50# Organic Matter 3% 100# (Pending Quality Ash or Humus) Crop Residue-(Soy/Clover) 30-50 N. Recharge (If surface decayed) Green Beans- 50# Nitrogen Fixing Bacteria 0-60 Plus # (Fixing Nitrogen form the air) Total: 275# INFLUENCE OF SOIL FERTILITY PRACTICES ON AGRICULTURAL PESTS John M. Luna, Assistant Professor, Dept. of Entomology, Virginia, Polytechnic Institute and State University, Blacksburg, VA 24061, USA The role of competitive organisms in disease suppression and its enhancement by the addition of organic matter has been know for many years. A 1958 study by Adkisson reported nearly three times as many boll weevil larvae in cotton fields receiving heavy applications of fertilizers compared to unfertilized fields. Zinc deficiency reduced the pubescence on corn leaves which allowed a subsequent increase in feeding by adult western corn root worm. High nitrogen fertilization is known to increase the susceptibility of pear to fire blight, of tobacco to wildfire and the tobacco mosaio virus, and of wheat to rust and various forms of powdery mildew. Increases in nitrogen rates dramatically increase aphid and mite populations. Garman & Kennedy (1949) noted that the density of the two spotted spider mites increased in beans and peaches as the rates of N, P & K were increased. Have a Nitrogen Plan Lead Time For: Crop Need Vegetables Fruits Cover Crop Used Crop Residue Compost and/or Manure Applications Aim for achieving balance Consider feather meal, or fish emulsion for short-term release Mammoth-Clover with Sweet Clover Old Stand By Good when short on Nitrogen in rotation with vegetables (Usually during the beginning years) Better weed control Benefit if left 2 years as hay or seed crop 3

11/25/2013 Weeds are Indicators Weed are Indicators All Weeds Small Grain Buckwheat Lambsquarters-Good Nutrients Velvetleaf-High Potash Alfalfa Quack Grass-Poor Calcium Solubility Palmer Amaranth (Pigweed)- Improper Phosphate & Potash Jimson weed Poisonous Improper Decay in High Organic Matter Soils 19 Cover crop, small grain Next years planting starts at this years harvest Allelopathy effect Broadcast cover crop and lightly disc in. Conventional lfield worked kdwet Added Nitrogen but has Nitrogen deficiency in tracks Soil needs oxygen to function #1 Problem in US Ag is compaction Rye Cover Crop (Cardinal Rule don t work the soil wet in the spring) Rye cover crop-work in young for nitrogen, weed control effect (allelopathy). Could be rotovated. Rye broadcast in November, in snow and worked in. If let to grow tall- C/N ratio changes and more organic matter is built. Avoid dual wheels in spring, radial tires preferred for higher horsepower Next years planting starts at this years harvest. Next year s planting starts with this year s harvest. Wheat harvest Oat cover crop Cover crop, small grain stubble Allelopathy effect Responsibility to keep it green Broadcast Cover crop and lightly disk in. Reason for Grass ~vs~ Legume cover crop 4

11/25/2013 Clover cover crop worked in with an offset disk and chisel plowed. Mix and decay Field of Corn after Corn Working Clove Cover Crop Clover & Alfalfa can be moldboard plowed if time is a factor Could be rotovated Organic surface tillage Why do some farmers moldboard plow for weed control? Notice decay of stalks by second cultivation. Flamer Bi-directional Cultivator July 2, 2010 Corn: can do multiple flamings Beans: only early stage (2 leaves) Above picture: Cultivator and tine harrow throwing the dirt up and under the bean leaves. Bi-directional Cultivator July 2, 2010 Technology and Innovations Above picture: Driving forward with the cultivator in front. Auto Steer Uses global positioning technology Maintain straight rows Returns to same rows for operations later Don t have to touch the steering wheel Most anyone can do the work Above picture: Showing the tine harrow while driving forward with the cultivator in front. 30 5

11/25/2013 (Brown is Best) Liquid Manure Less offensive odor if from aerobic~vs~anaerobic pit Aerobic digestion builds organics Anaerobic digestion tears down organics Good Health High Humidity : Low Humidity (Michigan : Colorado) Increased beneficial biology Increased unbeneficial biology Effect on taste and flavor Apples Effect on navy bean skins Vibrant Health Beneficial The Circle of Resistance Disease Pests Bad Health Your Farm is an organism, so where does your farm or orchards health fall in the floating circle of resistance? If Managed properly, you can move your circle more into Good Health. For more information on our services please contact us at: Marlette, Michigan 48453 (989) 635-2864 phone (989) 635-3888 fax Bio-systems@centurytel.net 6

Cover Crops: A Valuable Cultural Component of Your Organic Weed Management Toolkit James DeDecker MSU Extension Agriculture Educator Restriction of synthetic herbicide use in organic agricultural systems increases the complexity of weed management, leading organic farmers to cite weeds as the greatest barrier to organic production (Walz, 1999). To meet this challenge, most organic growers employ a wide range of tools in an integrated weed management system. Our 2011 survey of Midwest organic farmers found that respondents used an average of fifteen (1-34) practices that contribute to weed management (DeDecker, 2012). The ten most commonly adopted practices for the 2010 season were crop rotation (86%) averaging 2-4 crops in sequence, between-row cultivation (78%), primary tillage (76%), cover cropping (66%), delayed planting (65%), green manure (63%) scouting (57%), hand weeding (57%), mowing (52%), and increased planting density (50%). This supports previous work finding that organic weed management is dominated by cultural and direct mechanical controls (Walz, 1999). Aside from crop rotation, which may not be motivated primarily by weed management needs, cover cropping is the most popular non-mechanical weed management tool available to organic growers. Our research also indicated that use of cover crops for weed management increased with additional farming experience, suggesting that growers come to value this tool over time, but may need to graduate to the complexities of cultural weed management. To be clear, cover crops are crops grown between harvest and planting of commodity or feed crops, usually not for harvest, but used instead for the production of biomass and the various agroecological benefits this additional biomass can provide. While cover crops are most often thought of as a means of preventing erosion and improving soil health, they can also be applied as an effective weed management tool. Cover crops can suppress weeds in four primary ways: 1) By diversifying and filling gaps in a crop rotation; 2) By competing with weeds for light, nutrients and moisture; 3) By releasing chemicals that inhibit the germination and growth of weeds (allelopathy); and 4) By attracting beneficial organisms that feed on weeds and weed seed. The following will expound a bit on how each of these suppressive mechanisms function and can be successfully applied. Diversifying and filling gaps in a crop rotation Diverse crop rotations suppress weeds by forcing them to grow in different crops with varying life cycles, growth habits, spatial arrangements, and management requirements. Rotating dissimilar crop species also allows the application of a wide range of control measures and exposes weeds to more natural mortality factors. For example, adding a year or two of a perennial legume crop like clover between annual vegetable crops can reduce the germination of annual weeds normally triggered by soil disturbance and also permits regular mowing that can suppress problem perennial weeds like Canada thistle. It is also important to remember that many weeds are pioneer species that tend to establish quickly and thrive in disturbed habitats. Gaps in a crop rotation that leave bare soil exposed create the ideal environment for weed growth. While mechanical control methods like cultivation can knock back weeds for a period time, any farmer knows that this effect is only temporary. Disturbing the soil essentially resets the successional clock, bringing new weed seed to the soil surface and initiating more weed

germination and growth. While it may be possible to till frequently enough to keep weeds down, tillage degrades soil health and tillage equipment is costly to operate. Cover crops can be grown in short windows before and after cash crops to fill gaps in a rotation and minimize the exposure of bare soil. Filling-out a crop rotation, keeping fields green year-round, limits the ability of most weeds to germinate and become established. For example, research at MSU s Kellogg Biological Station found that oilseed radish grown following snap beans reduced weed biomass 98.5% compared to plots left bare after beans were harvested (Figure 1). What weeds are able to gain a foothold in a growing cover crop will be much less vigorous as they are forced to compete for the necessities of life. Figure 1. Cover crops following snap beans suppress weeds. LSD @ 0.05 weeds-990, cover crops-1020. Source: Mutch and Martin, Kellogg Biological Station, Michigan State University. Competing with weeds for light, nutrients and moisture Plants need light, nutrients, moisture and CO2 to survive. The more plants that are present in a field, the less of each there will be available to go around. A vigorously growing cover crop, whether alone or interplanted with a cash crop, can prevent weeds from germinating and/or growing to the point that they produce seed or compromise cash crop yields. However, successfully applying this strategy requires knowledge of weed ecology, careful selection of cover crop species, and favorable conditions for cover crop establishment and growth. For example, a 2005 study by MSU s Dr. Dan Brainard found that sorghum-sudangrass, a tall tropical grass, planted in July following an early season vegetable crop reduced overall weed biomass 91% and the seed production of Powell amaranth (pigweed) by 95% compared to a bare ground control. However, in the same study, soybean used as a cover crop only reduced weed biomass by 59.3% and Powell amaranth seed production by 57%. Why such dramatically different implications for weed control based on cover crop choice? The most basic issue in that comparison was cover crop stature. Sorghumsudangrass grows quickly in mid-summer to form a full canopy that blocks light from even tall weeds like pigweed. Conversely, soybean can be slow to establish in dry summer soil and will never grow tall enough to shade rapidly developing pigweed plants. Sorghum-sudangrass is also one of the cover crop species known to produce allelopathic compounds, but more on that later. Unfortunately, the competitive impact of cover crops is not restricted to weed species. Research has shown that cover crops capable of out-competing weeds will likely also suppress an interplanted cash crop. For example, a 1998 study by Brandsaeter et al. found that a white clover living mulch suppressed

both weed and cabbage growth. In the case of living cover crops, cash crop suppression is most often the result of competition for water. Cover crop residues can also negatively impact the establishment of a cash crop. This is usually related to physical interference with seed placement in the soil, prevention of soil warming, tie-up of nitrogen, or the release of allelopathic compounds. Releasing chemicals that inhibit the germination and growth of weeds Some cover crops produce compounds that inhibit the germination and growth of other plants, including weeds and crops. This property is known as allelopathy. Known allelopathic cover crop species include cereal rye, hairy vetch, crimson clover, buckwheat, alfalfa, barley, rapeseed, oat and sorghum. Allelopathic compounds are present in the roots and above-ground portions of these plants in varying concentrations, and can act against weeds while the cover crop is alive and growing, or when cover crop biomass is incorporated into the soil. In some cases, the phytotoxicity of allelopathic compounds is increased when they are modified by soil microbes in the process of decomposition. Small seeded weed and crop species seem to be most affected by allelopathic compounds due to their greater surface-to-volume ratio and orientation nearer the soil surface where allelopathic crop residues are usually concentrated. Unfortunately, allelopathic effects can be difficult to isolate and apply in the field. This is because the suppressive effect created by these cover species is a combination of allelopathy and the sort of runof-the-mill plant competition described in the earlier section. Also, the production, activity and decomposition of allelopathic compounds can be highly variable based on environmental factors like soil fertility, moisture, ph and temperature. In general, the allelopathic effects of cover crop resides are quite short lived and hard to predict. Attracting beneficial organisms that feed on weeds and weed seed The final mechanism through which cover crops can suppress weeds is predation. Weeds are an important source of food for many organisms. While most weed predation is focused on seeds, various organisms prey upon weeds at every stage in their life cycle. While weeds are growing, birds, insects and microbes prey on every plant part. Once seeds are produced and fall to the ground, insects, rodents, earthworms and microbes can quickly devour a large percentage. A 2003 study found that rodents and invertebrates consumed 90% of giant ragweed seeds left on the soil surface in the course of one year (Harrison et al., 2003). Including cover crops in your system increases and diversifies the habitat available to these weed predators and encourages their presence. This approach of supporting populations of control agents that already exist in a field is known as conservation biological control. Conservation bio-control of weed predators can function in a couple of different ways. Planting and/or maintaining between-field cover in the form of herbaceous strips, fence rows and hedge rows provides habitat for weed predators year-round and increases their abundance (Menalled et al., 2001). Including cover crops within a field provides protection for weed predators, encouraging them to stay in the field longer and eat more weed seed. A 2003 study by Adam Davis and Matt Leibman comparing spring wheat alone to wheat underseeded with red clover found a two-fold increase in giant foxtail seed predation rates in the system including a red clover cover crop (Figure 2). A similar effect could likely be achieved in vegetable systems, such as buckwheat seeded into early season broccoli or kale. There is also strong evidence that reducing tillage to leave weed seeds on the soil surface contributes to increased seed predation.

Percent giant foxtail seed removed per day 100 80 60 40 20 wheat wheat + red clover 0 8-Aug 18-Aug 28-Aug 7-Sep 17-Sep 27-Sep 7-Oct 17-Oct Time (end of 4 day measurement period) Figure 2. Predation of giant foxtail seeds in wheat was increased by overseeding with red clover. Source: Davis and Liebman, 2003. Conclusion Cover crops can enhance many aspects of your organic farming system, including weed management. However, there are lots of cover crop options, and each farming system is different. Successful use of cover crops for weed management depends on strategic implementation. Several things to consider before planting a cover crop include: a) Is a particular species/variety likely to fit your objective of weed suppression via a particular mechanism?; b) Is the seed readily available at an acceptable cost?; c) Is the cover crop suited to your field conditions, soil, cropping system, traffic patterns, etc?; d) Is there a high likelihood of good establishment given your equipment and labor availability, timing, etc.?; e) Do you have a viable strategy for suppression and residue management?; and f) Is the cover crop likely to cause any additional problems due to weediness, insects, etc.? If you can satisfactorily answer all of these questions, the cover crop under consideration might be right for you and contribute to your success with organic weed management. References Brainard, D., Bellinder, R. and Kumar, V. 2011. Grass Legume Mixtures and Soil Fertility Affect Cover Crop Performance and Weed Seed Production. Weed Technology 25, No. 3, 473-479. Brandsaeter, L.O., Netland, J. and Meadow, R. 1998. Yields, Weeds, Pests and Soil Nitrogen in a White Cabbage- Living Mulch System. Biology, Agriculture and Horticulture 16, 291-309. Davis, A. and Liebman, M. 2003. Cropping System Effects on Giant Foxtail (Setaria faberi) Demography: I. Green Manure and Tillage Timing. Weed Science 51: 919-929. DeDecker, J. 2012. Weed Management Practice Selection Among Midwest U.S. Organic Growers. Unpublished Master s Thesis. University of Illinois Urbana-Champaign. Harrison, S., Regnier, E. and Schmoll, J. 2003. Postdispersal predation of giant ragweed (Ambrosia trifida) in notillage corn. Weed Science 51: 955-964. Menalled, F., Dauer, J., Fox, T. and Renner, K. 2001. Managing Your Farm to Increase Weed Seed Predation. Bulletin E-2749. Michigan State University Extension. Walz, E. 1999. Third Biennial National Organic Farmer s Survey. Santa Cruz, CA: Organic Farming Research Foundation.