Enhancing Sustainability of Organic Broccoli Production through Integration of No-tillage and Farmscaping
This proposal seeks to develop an improved organic production system for broccoli and other crucifer crops by integrating high-residue no-tillage (NT) systems to suppress weeds with farmscape plantings as a food and habitat for beneficial insects. Cover crops will be established on raised beds and mechanically killed before transplanting twin-row broccoli. NT fields will be farmscaped with a combination of living cover crops in the alleyways between beds, habitat plantings on bed tops, and trap crops grown in field peripheries. Both an overwintering cover crop mixture (grass and legume) for early NT broccoli and a summer crop mixture for late NT broccoli will be farmscaped and evaluated for organic weed and insect control. Research will include a highly detailed experiment at Virginia Tech and a less-detailed on-farm research-demonstration plots at five sites in Virginia and North Carolina. No-tillage will be compared against conventional (inversion tillage) systems at all locations. Three research/outreach collaborators will help implement the on-farm experiments. The collaborators and farmer participants are active members of organic grower organizations and will serve as a nucleus of an outreach and technology transfer program that will ensure immediate and long-range impacts.
In October 2003, cover crops were successfully established at Virginia Tech and three on-farm sites. In June, organic broccoli NT-farmscape systems will be established at all locations. Awareness of and interest in NT-farmscape systems appear to be high among organic growers, as a result of the expertise and extensive outreach activities of the project coordinator and collaborating participants.
Objectives—Our hypothesis is that by integrating farmscaping with NT systems, broccoli production can be economically feasible without application of chemical pesticides. We will demonstrate that high-residue cover crop mulch combined with farmscaping, augmentation with natural enemies, and timely use of the microbial pathogen Bt can suppress weed and insect pests to produce a profitable organic broccoli crop. Specific objectives are to (1) develop an improved prototype system for production of organic broccoli by integrating high-residue NT cover crop mulch to suppress weeds and supply organic nitrogen with farmscape plantings to attract and sustain beneficial insects; (2) evaluate the need for application of Bt in farmscaped systems for broccoli to control insect pests; and (3) facilitate the adoption of high-residue NT production systems and farmscaping by organic growers, using on-farm demonstrations and other education and outreach methods.
Performances targets—By December 2005, four fact sheets and a comprehensive leaflet on organic NT-farmscape broccoli production will be available in both electronic and printed form. Within one year after completion of the project, (1) two of the five organic growers hosting on-farm demonstrations will adopt NT-farmscape systems, and (2) ten of the 200 or more growers who will attend workshops and field days will explore NT-farmscape systems for production of organic broccoli or other crops.
Research—In 2003, record rainfall occurred at the Virginia research site (Kentland Agricultural Research Farm, near Blacksburg), which prohibited timely land preparation and seeding of cover crops needed for the proposed fall/2003 broccoli crop. Thus, a no-cost time-extension will be required to complete the project and allow planting of a fall/2005 broccoli crop (in place of the originally proposed fall/2003 crop). By late summer, the rains did subside enough to allow land preparation and planting a fall cover crop of cereal rye and hairy vetch. The stand and uniformity of the rye/vetch biculture is excellent and should provide a high-residue mulch for a late spring/2004 NT broccoli crop. Both insectary (habitat) and trap crop plantings will established in mid spring in the designated farmscape subplots.
Outreach/on-farm demonstrations—As with the research site, excessive rainfall prohibited timely land preparation and seeding cover crops at all previously identified farmer-participant sites. Thus, the fall/2003 demonstration trials will be replaced with fall/205 plantings. Fall-seeded overwintering cover crops were successfully established at three on-farm sites. Farmscape plantings will be established in mid spring and broccoli will be transplanted in the high-residue NT mulch plots in early June.
Outreach/increased grower awareness—Many organic growers in Virginia and North Carolina are aware of and have expressed interest in our project. Examples of outreach activities by the project coordinator and outreach participants include:
(1) Presentations were given by Ron Morse and Mark Schonbeck on organic NT vegetable production and biological soil management at the Virginia Biological Farming Conference in Wakefield, VA on January 30-31, 2004. About 60 people attended. Presentations on organic NT vegetable production and on biological soil management were given at the High Country Organic Growers School in Boone, NC on March 27, 2004. About 25 people attended. A 4-page information sheet on cover crops suitable for organic NT systems was prepared for both events.
(2) A grant proposal has been submitted by Mark Schonbeck and Ron Morse to the Organic Farming Research Foundation (OFRF) to conduct supplemental experiments comparing several cover crops as winter-killed mulch for spring organic NT broccoli production. The proposal requests $8,600 in funding; grant awards will be announced in late April, 2004.
(3) Richard McDonald produced and launched a highly technical website manual to train transition burley tobacco growers. This manual features organic broccoli production techniques, soil health basics, broccoli enterprise crop budgets, farmscaping, and organic broccoli pest management. The website is free and open to everyone (www.drmcbug.com).
(4) In 2003, tobacco growers transitioning to organic vegetable production successfully produced and marketed organic broccoli. For example, Watauga River Farms produced a total of 8,500 pounds of high quality organic broccoli on one acre (spring and fall crop), using biologically based IPM (BIPM) farmscaping methods. BIPM expertise and training was provided to the New River Organic Growers Association to further their transition to organic broccoli production, as specified in the grant proposal.
(5) The BIPM/farmscape program for organic broccoli was featured at three Carolina Growers Schools: Coastal Organic Gardening School, 28 February 2003; Organic Vegetable School, Ashville, 15 March 2003; and the High Country Organic Growers School, 22 March 2003.
(6) The BIPM/farmscape program for organic broccoli has also been featured in the following magazines: Common Ground, Fall/2003; Appalachian Today, Fall/2003; and Watauga County Extension News, Spring/2003 and Fall/2003.
(7) Richard McDonald taught three classes to a total of over 350 students on farmscaping and beneficial insects at the 11th Annual Organic Growers School at Blue Ridge community College in Hendersonville, NC.
(8) On 21 September 2003, a farm tour was held in Watauga County, NC, featuring organic broccoli production and our farmscaping methods; 31 people attended.
Impacts and Contributions/Outcomes
Although this SARE project is just in its infancy, we are very optimistic regarding future impacts leading to more sustainable and profitable methods of organic production of broccoli and other vegetables. We also anticipate that we will develop NT equipment and associated technology for small-scale (1-3 acres) organic growers.
Appalachian Sustainable Development
Department of Entomology
Blacksburg, VA 24061