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At Anne and Eric Nordell's Beech Grove Farm in north-central Pennsylvania, horses, cover crops, and reduced tillage add up to "bio-extensive market gardening"

Bio-extensive market gardeing at work: Draft horses, alternative tillage techniques and cover crop rotations are all part of the mix on Beech Grove Farm.

Posted January 7, 2005:Imagine assembling a self-contained, regenerative farming system… and making a living doing it. Impossible, you might say—but over the last 20 years Anne and Eric Nordell of Beech Grove Farm in Trout Run, Pennsylvania, have been doing just that. What’s their secret? Draft horses, alternative tillage techniques, and a time-tested rotation of cash and cover crops. They call their system “bio-extensive market gardening."

Although neither Anne nor Eric was raised on a farm, together they’ve turned a 6-acre market garden into an ecologically sustainable enterprise. Their fields are divided into 12, half-acre plots roughly 120 yards long by 20 yards wide. Each plot follows a single-run cropping system consisting of rows 34 inches apart. “The shape of the fields reflects my experience growing corn more than anything,” Eric explains. “It lends itself to using horses.”

Because of the farm’s rural setting in north-central Pennsylvania, the Nordells began by growing cool-season, non-perishable crops such as roots, alliums, and medicinal herbs. Before long, requests from local upscale restaurants for dependable supplies of high-quality leafy greens led the Nordells to add leaf and fruit vegetables to the mix. In the beginning, Anne recalls, “the last thing we wanted to grow was perishable crops."

Anne and Eric Nordell harvesting garlic

Over the last three years, gross sales can be analyzed as follows:

Although the type of produce they grow has changed over the years, the Nordells' objectives are still the same: utilize on-farm resources, remain a two person operation, and stay debt-free by minimizing costs. Rather than chase gross income, Anne and Eric have sought to do what is right for the land, their customers, society, and themselves.

Beech Grove Farm has been certified organic since 1988. The Nordells first sought certification because their wholesale accounts—two growers’ coops, two distributors, and Walnut Acres, a mail-order business—began demanding it. As their sales shifted from predominately wholesaling out of the area to direct marketing more locally, certification became less important. But despite some reservations about federal involvement, the Nordells have chosen to maintain their certification because it distinguishes them at the farmers’ market, it allows them to sell to local stores, and it helps to educate both growers and consumers about organic practices. Contrary to some farmers’ experience, they say certification takes less time and paperwork today than it did before creation of the National Organic Program. Because of the cost-share program, it’s more economical as well. And since the Northeast Organic Farming Association of New York already had a rigorous certification program, the federal standards have not been difficult for the Nordells to meet.

Photo by Steve Vanek, courtesy of the Northeast Organic Network (NEON)

“One of the nice things about horse farming is that the horses are constantly producing fertility.”

When Anne and Eric began farming, they used tractors for some tasks and horses for others. But over time they found that the tractor just didn’t pay. “I didn’t think that horse farming alone would even be possible,” admits Anne.

Today they keep four draft horses, an experienced pair and a pair in training. Although the Nordells have to purchase feed (oats, hay and minerals) and bedding (straw and other materials) for the horses, these off-farm inputs result in more than just feed and bedding. They equal fuel and fertility. “One of the nice things about horse farming is that the horses are constantly producing fertility,” Eric says with a smile.

The Nordells have developed an innovative method for composting the horse manure to control temperature and stabilize nitrogen. Peat moss and straw are spread at the rear of the stalls to absorb urine and manure. Since the horse stalls are located near the pig pens, the soiled straw and peat moss can easily be moved into one of three 'composting' pig pens. The rooting instinct of pigs is harnessed by drilling some feed into a hole in the used bedding. The pigs root in the pile, turning the compost and helping to control temperature and odors. Through intensive pig composting, manure can be applied to the field in just six to eight weeks.

Happy as a pig in...well...: The Nordells have discovered their hogs are the key to an innovative composting method.

The Nordells only compost and apply manure generated by their own four horses. Compared to many market gardens, the rate of application per acre is low. But unlike traditional market gardeners, the Nordells apply compost to cover crops, not their cash crops. The cover crops contribute to soil health and in turn fertilize the cash crops. This also avoids flushes of weeds during cash crop years due to nutrient excesses or imbalances.

The compost that isn’t applied to the fields is further turned and worked by laying hens. The action of the chickens scratching creates a fine potting mix. The Nordells raise their own seedlings in an innovative, energy-efficient hothouse heated by a woodstove. The stove's flue pipe runs beneath the propagation table, surmounted by a layer of rock that acts as a thermal sink. The Nordells simply make a fire at night and go to bed. Because the rocks absorb the heat and hold it over night, there’s no need to stoke the fire in the wee hours. The system combines convenience and economy. "It only costs us $70 every two years to heat the hothouse with slab wood,” says Anne.

The bio-extensive market garden

Each field rotates between a cash crop and cover crops every other year. The cash crops alternate between early and late, while the cover crops rotate between winter-kill and over-wintering. Winter-kill cover crops, like oats and peas, precede early cash crops, while over-wintering cover crops, such as rye and vetch, precede late cash crops. The following sequence is a template for a four-year rotation:

Year 1	spring	rye
	summer	bare fallow
	fall	oats and peas (winter kill)
Year 2	spring	early crops
	summer	clover
	fall	clover
Year 3	spring	clover
	summer	bare fallow
	fall	rye and vetch
Year 4	spring	rye and vetch
	summer	late crops
	fall	rye

At first glance, you’ll see that the cover crop years incorporate a six-week summer fallow. Deep plowing and successive tillage create a series of stale seedbeds, which germinate and terminate annual broadleaf weeds. These same weeds would compete with cash crops the following year, but are now eliminated from the soil’s weed seed bank. When preparing beds for cash crops in spring, the Nordells use shallow tillage to prevent new seeds from being brought to the surface.

What the above rotation plan doesn’t show are the various alternative tillage techniques used at Beech Grove Farm. The Nordells have made a firm decision not to use irrigation. Instead, they seek to conserve existing soil moisture. This is largely done by minimizing the depth of tillage.

Their alternative tillage techniques include mulch-tilling, ridge-tilling, no-tilling, and skim plowing. Mulch-tilling shallowly incorporates mature cover crops, leaving a mulch of cover crop residues on the soil surface.Ridge-tillinginvolves forming ridges and seeding them to cover crops the preceding fall. In the spring, the winter-killed cover crop is knocked off the top of the ridge, leaving a narrow strip of clean soil for direct seeding. No-tilling for the Nordells means slicing a narrow furrow into a cover-cropped ridge and transplanting or hand planting into the furrow. Skim plowing is used to shallowly incorporate over-wintering cover crops. Each of these alternative tillage techniques preserves the soil structure created by the cover crops' root systems, controls erosion, minimizes evaporation, and improves water infiltration, creating a large reservoir of moisture for cash crops.

Each alternative tillage technique is used with specific cover crops to coincide with target planting windows. Again, the cover crops are divided into winter-killed and over-wintering species; the planting windows can be generalized as early, mid-season and late. The following chart lists the tillage/cover crop regimes in chronological order:

Photo courtesy of the Penn State Agroecology on-Farm Undergraduate Internship Program

“a weed management plan involves prioritizing what weed is a problem, understanding its life cycle, and then targeting that specific weed.”

winter-killed cover crops
Tillage type		Cover crop		Planting window
ridge-till		oats & peas		early direct-seeded
no-till		oats & peas		early transplant
mulch-till		oats & peas OR sorghum-Sudan & forage soybeans		early transplant & mid-season direct-seeded

over-wintering cover crops
Tillage type		Cover crop		Planting window
skim-plow		rye & hairy vetch OR Italian ryegrass & clover		mid-season transplant & direct-seeded.
ridge-till		rye		mid-season transplant & late direct-seeded
mulch-till		rye & vetch		late transplant

Each combination adds more options to the original four-year rotation by fine-tuning planting conditions for a handful of growing windows. The Nordells follow a simple principle: Find the tillage/cover crop regime that allows the cover crop to be killed and tilled six to eight weeks before planting. This provides enough time for the breakdown of cover crop residues before planting and allows the soil to gather moisture for the cash crop.

Reduced tillage has presented a couple of problems at Beech Grove Farm, namely weeds and slugs. We’ve already seen how summer bare fallows and dominant cover crops address warm-season weeds. The Nordells are now experimenting with a spring bare fallow the year before early planted no-till crops to reduce cool-season weeds, like chickweed. Eric explains that “a weed management plan involves prioritizing what weed is a problem, understanding its life cycle, and then targeting that specific weed.”

The Nordells use trap crops and chickens to deal with slugs. Trap crops are plants used to attract pests away from valuable cash crops. For example, since slugs seem to prefer legumes, the Nordells have had some success planting beans in the pathways between carrots. The slugs naturally gravitate towards the beans and leave the carrots alone. Even more effective are the free-range chickens which the Nordells have worked into their cover crop rotation. During a fallow year, laying hens are grazed on cover crops and naturally feed on any slugs. For example, the clover in an Italian ryegrass and clover mix acts as a trap crop, attracting slugs from neighboring cash crops. The chickens clear the fallowed field of slugs, leaving a clean field for the following cash crop.

Who would have thought that a regenerative, in some ways old-fashioned agricultural system could meet the needs of a modern market? The Nordells’ Beech Grove Farm is proof that it’s possible. Rather than reap short-term profits through industrial efficiencies, they’ve sought to invest in long-term sustainability through ecological efficiencies. The farm's horses, complex rotations, and reduced tillage methods are not industrial technologies, but rather ecological technologies, truly sustainable and technologically appropriate. It's hard not to come away with an impression of Beech Grove Farm as a model of what sustainable farming could be. 

Its round-up time in slug country, partner: The Nordells free-range chickens are an integral part of their cover crop rotation for slug control.

Kyle Holzhueter has studied natural approaches to agriculture in Japan and environmental design in Australia. He hopes to develop a demonstration homestead and further the eco-village movement throughout North America after his current apprenticeship at the Camphill Village Kimberton Hills in Kimberton, PA.