Sustainability

Can No-Till Farming Go Big?

Illustrated by Ali Aas

While small-scale organic farmers have had notable success with the practice, widespread adoption faces significant hurdles.

It’s a farmer’s dream: rich, deep, black soil that grows abundant and healthy crops; soil that hosts a complex web of microbial life, and can absorb inches of sudden rainfall without eroding; soil that gets healthier, and more weed-free, every year. For many curious farmers, this is the promise offered by a transition to no-till farming.

Over the past several years, the no-till approach has been increasingly adopted by organic market gardeners, who typically grow intensively on a handful of acres and sell their produce through farmer’s markets, CSAs, and roadside stands. Through conferences, webinars, word of mouth, and several recent books, no-till has become a discussion item on the level of compost and soil testing.

Similarly, there has been an increased push toward no-till among larger, conventional row crop farmers, albeit with methods requiring increased chemical applications and costly specialized equipment. But so far, adoption of no-till methods among larger produce farms — those working 10 or more acres — has been relatively slow, and the techniques that work well on the small scale provide challenges when farming larger acreages.

Why not till?

Tilling soil — the widespread practice of turning over and breaking up soil — has well-documented harms in terms of soil health. Tilling breaks down the aggregates that provide pores for holding water and air, needed by both plant roots and soil microorganisms. The churning also breaks up fungal hyphae, the threadlike extensions that form a storage and transport network for beneficial fungi.

Tilling brings buried weed seeds up to the surface, where they can sprout, grow, and set seed. A single invasive pigweed plant can shed over 100,000 seeds in its lifetime, each of which remains viable for up to four years. The downward force of the tiller tines (or the moldboard plow) compacts the soil below, creating a “plow pan” that reduces root penetration to deeper soil layers. Moldboard plowing — the most aggressive form of tilling — churns the top 6-10 inches of soil to bury weeds and crop residue from the prior season. This in turn leaves the soil surface rough and uneven and requires additional tillage to smooth the soil surface before planting.

Finally, tilling hyper-aerates the soil, speeding oxidation and loss of valuable soil organic matter (SOM). For example, “the average level of soil organic matter in Massachusetts cropland is one to two percent,” according to Caro Roszell, soil health specialist with American Farmland Trust, “while among market gardens,” especially those who have converted to no-till practices, “it’s pretty typical to see eight percent or higher.”

Conventional vs. organic

Large-scale, conventional no-till or reduced-till growing has been on the rise for more than a decade, with an increase in acreage of 36% since 2012, according to the U.S. Department of Agriculture (USDA). In 2017, the latest year for which figures are available, there were over 100 million acres in the U.S. managed without tillage. In conventional no-till systems, herbicides are used not only to kill weeds, but to kill cover crops without plowing; according to the Environmental Protection Agency, about 280 million pounds of glyphosate (the most commonly used herbicide) is applied to American cropland annually.

Without tillage, many conventional farmers are forced to increase their herbicide application. This usually comes in the form of a “burndown” treatment — an additional, direct application before planting. A 2021 study by the Environmental Defense Fund found burndown herbicide purchase cost $9.97 per acre for corn and $15.62 per acre for soy. And while the reduced tillage that herbicides make possible can increase SOM, opinions are mixed on whether that level of chemical exposure is good for the soil, the farmer, or the consumer.

The organic approach to no-till is radically different. For farmers growing produce on a few acres or less, it usually involves the addition of significant amounts of compost to permanent growing beds, which replenishes nutrients, builds SOM, and buries weed seeds to reduce or prevent germination. Corinne Hansch, who, with her partner, runs the two-acre Lovin’ Mama Farm in Amsterdam, New York, applies several inches of a peat-compost mix every year, spending about 7% of the operation’s gross sales.

“My gut sense is that I think it has the potential to be less work, but it has not worked out that way yet.“

“Some people might consider that expense really high, but I think of it as an investment, and it has come back to us tenfold. It can be terrifying at first, but when you see the result — when you see no weeds, and the labor savings and the yield increase, all of a sudden you see it is worth every penny.” Hansch applies not only compost, but mulch as well, another common market farming approach.

Larger farms that grow organically without tillage often use a system developed by The Rodale Institute. The cover crop is terminated just before seed set using a roller-crimper, a heavy drum with rows of blunt blades that crimp the stem of the crop, rapidly killing it to leave a thick bed of mulch. The cash crop is then planted with tractor-drawn seeders or transplanters, modified to penetrate the mulch and reach the soil.

This system works well for large-seeded crops like corn and beans, which can grow up through the mulch, but is a challenge for crops with smaller seeds, like carrots. And as Rodale points out, “timing is everything” — rolled too soon and the cover crop will sprout up; too late, and seed will have set, interfering with the cash crop. Hot, dry weather at rolling time is ideal, while cool, wet weather may prevent full termination of the cover crop.

Challenges of transition

Larger organic farms have tended to look for solutions developed for tractor-based growing. “Equipment is probably the biggest challenge for larger-scale farms,” Roszell says. “A lot of this equipment is so new and unfamiliar to produce farmers that it feels like a big risk to be the first in your area to try it out.”

This equipment purchase is by far the largest cost in transitioning. Air seeders, no-till drills, and retrofitted tractors can all enable no-till farming, albeit at very different costs. A 2003 Oregon State University study analyzed equipment purchase strategies of 11 successful long-term no-till farmers. Farmers purchased, leased, or even retrofitted no-till drills at home for costs that ranged $21,508 to $102,662 (inflation-adjusted from 2003 USD).

Additionally, research has shown a common three-to-five-year period where a conventional farmer transitioning to no-till can experience a significant dip in yields, likely caused by shifts in the microbiome as the soil switches from bacterial to fungal dominance. Studies show that use of cover crops may help mitigate the yield dip during transition to no-till, but further research needs to be conducted. In the meantime, costly yield reductions can be enough to potentially scare larger farmers off from experimenting.

“I ... expected a point where the yields and economic benefits reached their peak, but they continued to rise. It was jaw dropping.”

For large-scale organic farmers, these challenges are compounded because they cannot use traditional herbicides to combat weeds. The Rodale methods aim to help, but these techniques are ineffective in some areas, and for some crops — it often requires a good amount of experimentation to figure out a workable approach. If farmers can apply several inches of compost all at once, they may be able to bury most annual weed seeds at one go. Applying less has its risks, though, as Hansch found out: “In our first year, we didn’t lay on enough compost, and got the worst of both worlds — horrible weeds, and horrible plant growth.”

The soil itself can also become challenging to work with during the initial transition. Farmers may see a significant increase in soil hardness as their perennially pulverized, low organic matter soil no longer receives its annual fluffing. The details differ by farm and soil type, but “it takes about five years for the biological processes to be able to restore good soil structure,” Roszell said, and if you need to add new practices to mitigate that increased hardness, such as subsoil ripping, “that might raise your costs.”

Additionally, the transition period can be quite labor-intensive. Jeremy Barker-Plotkin, who co-manages Simple Gifts Farm in Amherst, Massachusetts, is going into his 24th year of farming, his 17th at Simple Gifts, and third year of growing vegetables primarily without tillage. He uses two main systems: an “intensive” one that replicates the typical market garden, with farm-made leaf compost as a prime fertility source, and an “extensive” one, in which part of the acreage is set aside to grow a nutritive mulch (typically rye/vetch or oats/peas), which is then chopped, harvested, and applied to growing beds.

“My gut sense is that I think it has the potential to be less work, but it has not worked out that way yet,” said Barker-Plotkin, noting the additional labor involved in cutting and moving mulch, applying compost, and terminating crops without tilling.

Paydirt potential

For farmers that are able to ride out the challenges of transition, adoption of no-till practices can have significant long-term benefits. For instance, after rebounding from initial dips, many no-till farms experience yield — and profit — increases over time. A 30-year study out of Michigan State University, looking at commodity crop farms in the Upper Midwest, found that timeframe has a huge impact on no-till profitability. A third of farms in the study experienced initial profit dips during the transition to no-till, but after 13 years all farms achieved higher profitability than they had with conventional management. Study co-author Nick Haddad wrote in a press release, “Every year for more than 30 years, the yield in no-till treatments increased versus the yield in tilled treatments — every year. I would have expected a point where the yields and economic benefits reached their peak, but they continued to rise. It was jaw dropping.”

DeAnna and Kelly Lozensky, small grain farmers in North Dakota, were able to wean their 2600 acres off chemical inputs altogether following a decade of no-till. After testing the soil organic matter on their farm, the Lozenskys decided to stop fertilizing any field with over 3.5 units of organic matter. In the remaining fields, they executed a five-year plan to reduce fertilizer application by 20% each year until the soils were completely weaned off fertilizer — a significant cost reduction, with net benefits to overall farm sustainability.

Profits aside, one huge, self-evident benefit of no-till farming is the improvement to soil’s overall quality and resilience. Healthy, untilled soil not only holds more water than tilled soil, it also resists erosion from wind and water by as much as 80% more. Eric Odberg, a fourth-generation small grains farmer in Idaho, said his region’s recent drought put his soil resilience to the test. Last year when the Palouse region experienced its worst drought in 44 years, Odberg said many of his neighbors lost half their crop. His yields, however, remained 10 bushels higher than average. “They estimate we get an extra inch of water in no-till soils,” Odberg said.

The potential benefits are clear, but the challenges to a full transition remain daunting for many farmers — particularly large-scale produce farmers, who have fewer positive examples to learn from. In particular, organic farmers, who do not have the benefit of herbicide usage, may find no-till a challenge. Roszell anticipates that more large-scale farmers with positive no-till experiences will help provide examples for curious colleagues to emulate. DeAnna Lozensky remembers feeling nervous during her own farm’s switch, but after more than a decade of markedly improved soil quality, increased profits, and five years without fertilizers, she feels more confident than ever in her family’s practices. “We’re not only no-till,” she said, “we are never-till.”

Write for Ambrook Research.

Authors


Photo of Richard Robinson

Richard Robinson

Richard Robinson is a writer and farmer based outside of Boston. He farms Hopestill Farm, a family operation that dates back to the mid-1600s.

Photo of Caroline Noble

Caroline Noble

Caroline Noble is writer, reader, and consumer of all things agriculture. She currently manages climate initiatives for a family foundation in New York City.

Illustrative image of a person looking out a window at a field

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