Establishing and Evaluating Selected Cover Crops on Small Farms to Increase the Impact of Beneficial Arthropods on Crop Pests

Project Overview

OS13-079
Project Type: On-Farm Research
Funds awarded in 2013: $14,984.00
Projected End Date: 12/31/2016
Region: Southern
State: Florida
Principal Investigator:
Robert Hochmuth
University of Florida

Annual Reports

Commodities

  • Agronomic: buckwheat, rye, sunflower, triticale

Practices

  • Crop Production: cover crops
  • Natural Resources/Environment: habitat enhancement
  • Pest Management: Arthropod Habitat

    Proposal abstract:

    Sustainable agriculture in the South is increasingly practiced on small farms with limited resources by farmers who live on the farms and therefore are committed to enhancing environmental quality and conserving natural resources.  This situation requires that farms be economically viable, preserve the natural resource base, and enhance the quality of life for the farmers and their families.  Moreover, both large and small farms play an important role in supporting the competitiveness and sustainability of U.S. rural economies.  Southern farmers continue to face many challenges, including marginal profitability and uncertain economic security.  One key production challenge for farmers in the South is the cost of effectively managing the myriad of pests that infest their crops.  Southern farmers must combat many insect pests, diseases, and weeds almost year-round.  In particular, Florida is at risk of agricultural loss by invasive pests due to its expansive tourism industry (84 million visitors a year) and multiple ports of entry. Hurricanes have been blamed for introducing a number of economically important invasive pests into the Gulf States (Florida, Alabama, Louisiana, Mississippi, and Texas), and the region’s warm and humid climate is favorable for pest establishment.

     

    To support southern farmers’ efforts to manage pests sustainably, a unique, hands-on, whole farm “Living Extension IPM Field Laboratory”(Appendix A1 and A2) has been created at the University of Florida, Institute of Food and Agricultural Sciences (UF-IFAS), Suwannee Valley Agricultural Extension Center (SVAEC) with support from the USDA, NIFA EIPM-CS Program and the UF-IFAS Extension program (1, 2, 3).  This specialized IPM learning environment is used continuously to demonstrate how to enhance agro-ecological systems for specialty crop farmers and other clientele groups by adopting a diversity of beneficial cultural and ecological practices prior to use of chemical pesticides.  Thus, the IPM training program provides an infrastructure for delivering whole farm pest management practices.  Small farm specialty crop producers in the region have participated in training workshops at the SVAEC and now want to implement some of the sustainable IPM practices on their farms but require assistance in selecting appropriate cover crops and monitoring their impact on pest abundance and crop yields.  The practice of particular interest to the farmers is the use of cover crops to provide habitat for native beneficial arthropods but these practices have not been tested or demonstrated on small private farms in the region.

     

    Currently, there are few effective and well-coordinated research and outreach programs designed to help southern small-holder farmers manage their pest problems.  This proposal is designed specifically to help them manage pests in fruit and vegetable crops by evaluating, demonstrating and communicating the use of cover crops to create habitats for beneficial arthropods.  IPM practices in this proposal will focus on increasing types and abundance of beneficial arthropods that parasitize or prey on arthropod pests.  It is intended that these “first-adopters” will influence other farmers to plant cover crops to reduce the routine use of chemical insecticides.

     

    Statement of Proposed Solution: 

    The solution is to transfer beneficial arthropod and cover crop research results from the SVAEC and faculty in the southeast (4, 5, 6, 7) to local cooperating private farms by demonstrating the effectiveness of annual cover crops and associated natural enemies in  reducing reliance on insecticides. The 300-acre SVAEC is a showcase of best practices for ecological farm management  that includes: an eight acre pond, hardwood and pine forests, softened fence line vegetation, conservation tillage agronomic and horticultural crops, cover crops, invasive plant management, a transitional organic area, protected agriculture, fruit and nut orchards, and native plant habitats for beneficial arthropods (8, 9, 10, 11).  Trials at the SVAEC incorporate both annual and perennial crop habitat areas. Due to the short duration of this grant cycle, the focus of this research project will be on annual cover crops, including buckwheat, sunflowers, triticale, rye, sesame, and sunn hemp (12, 13, 14).  At SVAEC the best results were obtained by planting cover crops such as rye, triticale and sunn hemp in large blocks as a rotational crop on land after the cash crop was grown. Buckwheat and sunflower, on the other hand, were grown in strips within the cash crops.  Sunflower (Giganteus variety) was effective as a trap crop for stinkbugs.  Buckwheat planted in strips at SVAEC was the most effective in increasing beneficial arthropods (15, 16).  The research conducted at SVAEC showed the importance of making successive plantings of buckwheat throughout the year, every 30-60 days from March to November.

     

    The project will be conducted at Hoover farm located 12 miles and Rooney farm 8 miles from SVAEC.  Cooperators at both farms have participated in several trainings at SVAEC and expressed interest in implementing IPM practices on their farms.  The Hoover farm utilizes cover crops in their rotations for soil improvement, and both farms would like to include pest management in their cover crop planning.  In addition, the Hoovers collaborated with some members of this team (Hochmuth, Toro, and Treadwell) on a previous On-Farm SARE project to improve their organic fertility programs (17) and are experienced with on-farm research.  The planting strategy for this project will be to establish temporary cover crops and strips of cover crops within the cash crop production areas to increase beneficial arthropod populations in the cash crops.

     

    Farmer collaborators are interested in learning how the different approaches to cover crop integration, within and adjacent to the crop production area, will influence the density and diversity of beneficial arthropods and their effect on pests, crop quality and yield.  By comparing the history of insecticide use on the farms prior to cover crop integration for pest management with two years of data from this project, we anticipate a reduction in the frequency, quantity and type of insecticide applications; increased confidence and experience in cover crop use for pest management; and successful outreach to the broader farm community.

    Project Relevance to Sustainable Agriculture:

    The proposed on-farm research project supports several Southern SARE priorities, primarily “Beneficial Insect Habitat,” “Organic Agriculture” and “Increasing Sustainability of Existing Farming Practices.”  It will help to make agriculture in the South more sustainable by quantifying and delivering sustainable cover crop capabilities for enhancing beneficial arthropods primarily on small diversified farms in Florida and other southern states.  Planting low maintenance annual cover crops at strategic locations in association with cash crops on farms will provide a variety of cost-effective, sustainable ecological services.  Sustainability of southern farms can be increased by enhancing native populations of beneficial arthropods and increasing the ecological services provided by implementing whole farm IPM strategies (21, 22, 23).

     

    The ongoing use of cover crops at SVAEC has transformed unsustainable pest management practices based on weekly pesticide applications to infrequent spot treatment based on scouting and pest thresholds.  This remarkable conversion resulted in more than a 50% reduction in insecticide applications on the 300-acre farm over a three-year period.  Not only was there a reduction in overall number of insecticide applications, but selection of low-risk pesticides protected the beneficial arthropods.  Thus, the benefits of using sustainable cover crops on small farms in the Suwannee Valley have been proven but not yet delivered to local farmers.   

     

    Early adopting farmers will plant areas of cover crops and strip cover crops on their farms, resulting in reduced pesticide use and the creation of new opportunities to meet current consumer demand for agricultural products that are grown using sustainable methods.  During the three past years of the USDA, NIFA-supported IPM program at the SVAEC, more than 15 education and training events and tours have been conducted each year to serve a wide range of interested audiences: small farmers, county Extension agents, NRCS field staff, Master Gardeners, UF students, the Florida A&M Small Farmer Outreach Program, 4-H Youth Day Camps in Suwannee County, and many others.  Informed specialty crop farmers in the Suwannee Valley, especially beginning farmers, will readily adopt alternative IPM practices.  Eventually this model can be used by communities of farmers throughout Florida and the Southeast who are seeking more sustainable farming and land management practices.   

     

    All of the beneficial arthropods collected will be identified and counted, and a representative sample will be used to build a resource collection for training farmers and others.  The collection records will be documented in tables that include the species, number, date, location and crop.  Results of importance to the farmers will be graphed for presentation at training events, such as field days and UF-IFAS Small Farms Academy (SFA) workshops.  The IPM training through SFA will be offered in May or early June, 2015.  Cooperating farmers will share their experiences as a part of these trainings.  Yields will be compared between cash crops in association with cover crops and those grown conventionally on the cooperating farms.  All of the results will be widely available in publications and reports, and on websites.

               

    Project objectives from proposal:

    This on-farm research project is designed to demonstrate how to deploy cover crops on operating farms so that the species and populations of beneficial arthropods will be increased. We also will teach farmers how to increase their skill in identifying beneficial arthropods that are attracted to cover crops and how to maintain and enhance these populations on the farm year-round. The first step will be to map both private farms so farmers can visualize existing and future habitat locations relative to production areas and other farm features.  Next, research sites for the cash crops and cover crop strips on these farms will be selected by the cooperating growers.

    Strip plantings of cover crops, e.g., selected annual cover crops, such as buckwheat, sunflower, rye, triticale, sesame, sunn hemp and others, will be located on both farms, but there will be an emphasis on buckwheat cover crop strips for data collection purposes.  For the buckwheat cover crop strips, seeds will be planted using a seeder from the farms or a small no-till drill from SVAEC. Strips of cover crops will be established using best management practices for fertilizer, irrigation and weed management on the two farms.  Trials conducted at SVAEC showed the importance of providing adequate water and fertilizer (300 lbs/A of 13-4-13) for buckwheat plots in the dry, deep, sandy soils typical of the Suwannee Valley. On the Hoover farm, plots of buckwheat and other annual cover crops will be established adjacent to or in strips within the seven acre cash crop fields to be protected, e.g., squash, cucumber, pepper, tomato, eggplant and leafy greens.  On the Rooney farm, there is no idle land because blueberry and blackberry are permanent plantings; therefore, cover crops will be planted in drive rows and around the perimeter of the five acre field.

     

    The cover crop plots will be planted beginning in summer 2014.  The planting strategy will follow a schedule so that cover crop habitat is maintained year-round.  This strategy is essential to maintain beneficial arthropod populations at high levels because they need pollen and nectar sources as well as physical habitat.  The cover crop plantings on these farms will provide habitat for several beneficial arthropods that parasitize or prey on pests.  Based on three prior years of observations and monitoring beneficial arthropods in such plantings, the populations increase very quickly, within one year from establishing the habitat areas.  Beneficial arthropods commonly found included lady beetles, a diversity of parasitic wasps, big eyed bugs, spiders, assassin bugs, minute pirate bugs, lacewing larvae, syrphid fly larvae, and many species of native pollinators.  Experiences with a selection of mixed crop species will help guide the crop selections.  Much is known about various crops that attract beneficial arthropods but it was unexpected to determine that sesame is incredibly attractive to many large native pollinator species, more attractive than most historically preferred plants.  Sesame has a very large funnel shaped flower and abundant extrafloral nectaries making it a high value habitat crop (18). Sesame will be included in a mixed species cover crop during the warm season months to determine its attractiveness to natural enemies and pollinators on cooperating farms.

     

    Data will be collected in three sets of buckwheat cover crop strips and adjacent cash crops as well as from three cash crop areas without buckwheat strips at each farm. Pest and beneficial arthropods will be sampled in the plots and crops weekly beginning when the plants first start to grow and support arthropods.  Ten sweep net samples will be made in the center of each of three buckwheat plots, three adjacent cash crop areas, and three cash crop areas without adjacent buckwheat plantings. Each of the three experimental cash crop areas with buckwheat will be a minimum of one-half acre and each of the experimental cash crop areas without buckwheat will also be a minimum of one-half acre. The arthropods from each sample will be placed in a plastic bag and returned to SVAEC to be identified to species, if practical.  Taxonomic support is available from the UF-IFAS Entomology and Nematology Department (19).  Otherwise the taxonomic family will be noted or type of arthropod, e.g., spider.  A representative sample of the arthropods will be preserved and retained at SVAEC.  Data on the relative abundance of pest and beneficial arthropods in the plots and crop yields will be analyzed using analysis of variance (ANOVA) using JMP v.9 software (20).  Additionally, the type and abundance of pest and beneficial arthropods will be compared through time to assess their rate of establishment from the beginning of the project.  Cover crop development, biomass production, and ecological variables, such, rainfall, etc., also will be noted.

     

    These farms will be demonstration sites for farmers in the region to visit.  The two cooperating farmers will fully participate in the project and serve as first adopter leaders to encourage other farmers to adopt cover crops.  The full project team, including both farmers, will visit both farm sites once a year to assess the progress of the research.  The farmers will learn from each other and advise the team on any project improvements.

                Literature Cited:

               (1) Stevenson, T. 2013. A living laboratory- UF Suwannee Valley Agricultural Extension Center

    http://www.suwanneevalleytimes.com/component/content/article/51-news-stories/975-9-12-13-a-living-laboratory-uf-suwannee-valley-agricultural-extension-center.html

     

    (2) Hochmuth, R. C. 2011. Making Integrated Pest Management Part of Your Farm Every Day.

    http://hos.ufl.edu/newsletters/vegetarian/issue-no-566

     

    (3) Hochmuth, R. C. 2013. Whole Farm Approach to Trap Cropping Strategies for Stink Bugs.

    (http://hos.ufl.edu/newsletters/vegetarian/issue-no-584)

     

    (4) McNeill, C. A., O. E. Liburd, C. A. Chase. 2012. Effect of cover crops on aphids, whiteflies and their associated natural enemies in organic squash. Journal of Sustainable Agriculture. 36:382-403.

    (5) Frank, D. L., and O. E. Liburd. 2005. Effects of living and synthetic mulch on the population dynamics of whiteflies and aphids, their associated natural enemies and insect-transmitted plant diseases in zucchini. Environ Entomol. 34:857-865.

    (6) Walton, N.J. and R. Issacs. 2011. Influence of native flowering plants on natural enemies and herbivores in adjacent blueberry fields. Environ Entomol. 40:697-705.

    (7) Tremelling, M. J., R. McSorley and R. Gallaher. 2003. Effects of winter cover crops on the soil surface invertebrate community. Soil and Crop Science Society of Florida Proc. 62:77-82.

    (8) NRCS. 2002. Conservation Practice Standard, Code 422- Hedgerow Planting.

    (http://efotg.sc.egov.usda.gov/references/public/NJ/NJ422.pdf)

     

    (9) Dufor, R. 2000. Farmscaping to Enhance Biological Control. NCAT. ATTRA-National Sustainable Agriculture Information Service.

    (https://attra.ncat.org/attra-pub/summaries/summary.php?pub=145)

     

    (10) Zehnder, G. 2013. Farmscaping: Making Use of Nature’s Pest Management Services. eXtension. (http://www.extension.org/pages/18573/farmscaping:-making-use-of-natures-pest-management-services/print/)

     

    (11) SARE. 2012. Whole-Farm Approach to Managing Pests.

    (http://www.sare.org/Learning-Center/Bulletins/A-Whole-Farm-Approach-to-Managing-Pests)

     

    (12) Treadwell, D., W. Klassen and M. Alligood. 2012. Annual Cover Crops in Florida Vegetable Systems Part 1. Why Grow Cover Crops? UF-IFAS EDIS publication, HS 387. (http://edis.ifas.ufl.edu/hs387)

     

    (13) Treadwell, D., W. Klassen and M. Alligood. 2012. Annual Cover Crops in Florida Vegetable Systems Part 2. Production. UF-IFAS EDIS publication, HS 1141.  (http://edis.ifas.ufl.edu/hs389)

     

    (14) Treadwell, D., W. Klassen, M. Alligood, and S. Shewey. 2012. Annual Cover Crops in Florida Vegetable Systems Part 3. Buying and Sourcing. UF-IFAS EDIS publication, HS 1142. (http://edis.ifas.ufl.edu/hs390)

     

    (15) Treadwell, D. and P. Huang. 2012. Buckwheat: A Cool-Season Cover Crop for Florida Vegetable Systems. UF-IFAS EDIS publication, HS-1135. (http://edis.ifas.ufl.edu/hs386)

     

    (16) Nyoike, T. W. and O. E. Liburd. 2010. Effect of living (buckwheat) and UV reflective mulches with and without imidacloprid on whiteflies, aphids and marketable yields of zucchini squash. International Journal Pest Management. 56:31-39.

     

    (17) Simonne, E. 2005. Optimization of irrigation practices in organic and sustainable vegetable production with soluble dye as an educational tool. SARE Project Reports. https://projects.sare.org/sare_project/OS05-026

    (18) Mizell, R. F. 2012. Many Plants Have Extrafloral Nectaries Helpful to Beneficials. UF-IFAS EDIS publication, ENY-709. (http://edis.ifas.ufl.edu/in175)

     

    (19) Buss, L. J. 2013. Insect Identification Service. UF-IFAS EDIS publication, RFSR010. (http://edis.ifas.ufl.edu/sr010)

     

    (20) SAS Institute. 2010. JMP Users Guide: Statistics. SAS Institute Inc., Cary, NC

     

    (21) Altieri, M. A. 1999. The ecological role of biodiversity in agroecosystems. Agriculture, Ecosystems and Environment. 74:19–31. (http://globalrestorationnetwork.org/uploads/files/ LiteratureAttachments/317_the-ecological-role-of-biodiversity-in-agroecosystems.pdf)

     

    (22) Smith, H. A. and J. L. Capinera. 2011. Natural Enemies and Biological Control. UF-IFAS EDIS publication, ENY-822. (http://edis.ifas.ufl.edu/in120)

     

    (23) Smith, H. A. and O. E. Liburd. 2012. Intercropping, Crop Diversity and Pest Management. UF/IFAS EDIS publication, ENY-862 (http://edis.ifas.ufl.edu/in922)

     

    Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.