Virginia Tech s Kentland Farm Grows Organic Produce for Dining Halls

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1 Virginia Tech s Kentland Farm Grows Organic Produce for Dining Halls By Mark Schonbeck November, 2010 From 2003 through 2007, I worked with Dr. Ron Morse of Virginia Tech on experimental cover crop-based organic no-till systems for vegetable production. Although continuous no-till has not proven practical without the use of herbicides, Dr. Morse and colleagues have identified many opportunities to increase cover crop biomass and nitrogen (N) contributions to soil fertility, maximize ground coverage, and decrease soil disturbance through what he now calls conservation agriculture. Biodiversity is enhanced through crop rotation, intercropping vegetable and cover crops, and farmscape plantings for beneficial insect habitat. He has developed several simple, affordable, tractor-drawn implements for conservation agriculture applications for small scale organic vegetable growers. His team continues to conduct research, demonstration, and organic vegetable production on six acres of USDA certified organic land at Virginia Tech s Kentland Agriculture Research Farm near Blacksburg. After a couple years hiatus in my involvement with conservation agriculture, I visited Ron at Kentland in July 2010 to learn of the latest developments. Perhaps the most exciting is that Ron is now working as Education Coordinator at Kentland Farm for a project that involves students in producing organic vegetables for the university s dining halls on the six certified acres. Major crops grown for the dining halls include broccoli, tomato, pepper, potato, and salad greens. In addition to providing fresh organic food for Virginia Tech students, the project offers a field practicum for student enrolled in a new minor in Civic Agriculture and Food Systems available to undergraduates through the College of Agriculture and Life Sciences (see sidebar). Sidebar: Virginia Tech offers Minor in Civic Agriculture and Food Systems A team of Virginia Tech faculty, staff, students, and community partners have developed an undergraduate curriculum for an 18-credit minor in Civic Agriculture and Food Systems (CAFS). The values of CAFS include food sovereignty, civic engagement, strong local economies, ecological stewardship, and healthy people and communities. The CAFS curriculum utilizes transdisciplinary approaches, collaborative teaching, and experiential learning to equip students to solve real-world problems related to agriculture and food systems. The CAFS minor includes four 3-credit required courses: Introduction to Civic Agriculture, Ecological Agriculture Theory and Practice, Concepts in Community Food Systems, and a VABF.org Page 1

2 Capstone course in CAFS in which students work with community stakeholders to develop viable solutions to real world community food system issues. In addition, students choose six credits of study from a list of electives. Choices include a field study practicum (such as organic vegetable production at Kentland for the dining halls), undergraduate research, and courses in sustainable development, food system economics, food and agriculture policy, leadership, communications in agriculture, livestock and the environment, community nutrition, and more. The CAFS minor was first made available this past year to students graduating in Currently, about 20 students are enrolled. Drawing on the system developed by Pennsylvania organic farmers Anne and Eric Nordell, Ron utilizes a crop rotation of one year in production and one year in cover crops, yielding excellent harvests on three acres. Broccoli yields have reached 12,000 lb/ac, and summer squash up to 30,000 lb/ac. Nutrient management is key, Ron emphasized as we walked among thriving vegetable fields, even salad greens that were succulent and appealing despite the summer s brutal heat (Fig. 1). Vegetables need plenty of nitrogen, balanced with other nutrients, especially potassium, Ron said. He showed me some experiments, not in the certified organic area, in which he is evaluating several legumes for providing nitrogen (N) for vegetable crops, including alfalfa, yellow sweetclover, ladino white clover, and medium red clover. The only other N applied is approximately 5 lb/ac through fertigation with liquid fish fertilizer. I like the red clover best, Ron said. It is easiest to establish and manage. [Note: we have also gotten into red clover at my home community in Floyd. Alleys between tomato crops seeded in late June were densely covered a foot deep in red clover by the end of September, and it was even slowing the growth of our worst weed, Canada thistle. MS] Figure 1. Salad mix growing on drip irrigation and with partial shade from an adjacent row of tall farmscape (beneficial insect habitat planting), yields quality greens despite the intense heat of the 2010 season. Ron also mentioned his work with the Virginia office of the USDA Natural Resources Conservation Service (NRCS) to develop cover cropping demo plots for farm scale application, VABF.org Page 2

3 and help draw up a menu of practices for the Environmental Quality Incentives Program (EQIP) Organic Initiative, designed specifically for USDA certified organic and transitioning-organic farmers. He invited me to participate in the Organic field Day at Kentland on August 17, and copresent with VA NRCS organic farmer contact person Ron Wood on conservation programs for organic farmers. Having represented VABF at VA NRCS State Technical Committee meetings for the past two years, and having just learned that the National Conservation Innovation Grant proposal in which VABF is a partner, had been approved, I gladly accepted. The August 17 field day was attended by about 30 people, and began with a potluck supper and brief presentations. Ron Wood discussed NRCS easement programs (such as the Conservation Reserve Program) and working lands programs (EQIP, Conservation Stewardship Program, Wildlife Habitat Incentives Program). He noted that 2010 is the 75 th anniversary for NRCS (established as the Soil Conservation Service during the Dust Bowl drought of the 1930s). I outlined the practice offerings for the EQIP Organic Initiative in Virginia. Susan Clark of Virginia Tech Dining Services discussed the new Civic Agriculture minor (see sidebar above), which was developed with funding from a USDA Higher Education Challenge Grant. She introduced student farm managers Jason Pall and Chelsea Graves, and former graduate student Brinkley Benson, who participated in creating the curriculum. After dinner, Ron Morse gave the farm tour, beginning with a demonstration of a plastic film mulch layer designed to work effectively in minimum-tilled or strip-tilled seedbeds (Fig. 2). He also showed the subsurface tiller-transplanter (SST-T) for setting vegetable starts through rolled or mowed cover crops (a major capital investment), and a no-till planting aid (NTPA), a simpler, lower-cost implement that prepares a narrow slot through the cover crop mulch for no till manual transplanting or seeding. Figure 2. Most plastic film mulch layers require a fine seedbed, obtained through intensive tillage that can burn up soil organic matter. This mulch layer, developed by Dr. Ron Morse, can operate in the rougher seedbed left by a light, shallow tillage pass to incorporate cover crops residues. VABF.org Page 3

4 The mini-ntpa shown in Fig. 3 is set up for transplants, and consists of a large, straight coulter to slice through residues, a shank to loosen soil deep enough for easy transplanting, and a drip tubing shoe for placing drip line precisely in the row. For direct seeding, the shank is replaced with a wavy coulter to work the surface just deep enough to sow seeds. The NTPA costs less than $1,000 and requires only 18 horsepower to operate two shanks. Figure 3. This no-till planting aid (NTPA) uses a heavy coulter and a shank to open a narrow slot through a rolled cover crop mulch, into which vegetable starts can be transplanted. A driptubing shoe (the yellow-colored device behind the shank) can be mounted on this NTPA, which enables drip tubing to be precision placed in-row and tucked under the cover crop mulch. Another recent equipment innovation is a band compost applicator (Fig. 4) that uses a shank to place compost in crop rows, some near the surface, and some further down in the soil profile to be accessed as crop roots grow. This implement allows effective crop nutrition from compost applications as light as two tons per acre, and requires a 50 horsepower tractor to pull two shanks. VABF.org Page 4

5 Figure 4. Ron Morse demonstrates a two-row compost band applicator that he designed to place compost throughout the root zone directly under crop rows. Ron discussed nitrogen management for the organic crops. He strives for a good balance among nitrogen (N), potassium (K), phosphorus (P), calcium (Ca), magnesium (Mg), and micronutrients. Legume cover crops are planted in the grow zone with weed-suppressive grasses in alleys. He estimates that the soil organic matter (which is now above 3%) yields about 60 lb plant-available N per acre per year, and the legume cover crops another 60 lb. This is sufficient for lower-n demanding crops like sweet potato. Broccoli needs 150 lb N to reach its yield potential, so he adds 30 or 40 lb N as feather meal, and finds that omitting this supplement can reduce yields by 3,000 lb/ac. Fertigation (Fig. 5) provides supplemental macro- and micronutrients to all crops, but adds only about 5 lb N/ac. Figure 5. Liquid fish fertilizer (yellow tank to right) is metered into the drip irrigation system that feeds all six organic acres plus other plantings at Kentland. The fish fertilizer is introduced VABF.org Page 5

6 after the well pump and before a sand filter, in order to minimize clogging of the drip lines, and filters are periodically back-flushed as needed. At this point, Jason Pall gave us a tour of the crops being grown for the dining halls. The emphasis is on crops that will mature during the undergraduate academic year, when dining hall demand is greatest. For example, winter squash and late plantings of summer squash begin yielding when the fall semester begins. Tomatoes set out at the beginning of June were beginning to yield at the time of the tour (a week or so before the semester began), and were free of disease without any sprays at all (Fig. 6). Figure 6. Jason shows the tomato and pepper crops, which are just beginning to yield as students return to Virginia Tech in late August to begin their fall semester. Jason noted that the field is ideally set up for moveable high tunnels, with sets of five raised beds alternating with wide grassed walkways. Although no high tunnels were in use at the time of the tour, they are an option under consideration for the future. We saw beds of bok choy (Fig. 7) and summer varieties of lettuce nearing maturity, and other greens recently planted and just coming up. Greens are succession-planted to provide continuous harvest into December. With plenty of irrigation and a little shade from taller crops in neighboring beds, the summer greens were yielding good quality salad mix at the time of the tour. VABF.org Page 6

7 Figure 7. A bok choy crop nears maturity, and will contribute to nutritious meals during the first weeks of the fall semester at Virginia Tech. Four rows of Irish potatoes were planted through flail-mowed rye + vetch, and cover crop regrowth was clipped with a weed whacker. There was no late blight in 2010, and farmscape plantings kept Colorado potato beetle in check by harboring its predators. Potato yields ranged from 12,000 to 21,000 lb/ac, an excellent result for so hot a summer. Jason showed us the snap beans, which usually give about two weeks harvest before bean beetles get out of hand. At this point, pyrethrin is sometimes used to kill the beetles before they spread to later plantings, and the crop is mowed and tilled in. Two plantings of broccoli cover about a half acre. Eight varieties of different maturity dates provide enough broccoli for all of Virginia Tech from the end of September through the middle of November. Fall broccoli is planted after a summer cover crop of soybean + sunnhemp in grow zones, with foxtail millet in alleys. So does CA mean Conservation Agriculture or Civic Agriculture? At this site, it means both (which is why I avoided the acronym here), as well as fresh organic food for Virginia Tech students. It is good to see research, practicum, and student nutrition so well integrated on six certified organic acres at this land grant university. VABF.org Page 7