Growing crops without disturbing the soil – or no-till farming – is hailed as a way of conserving and improving soil quality on arable land. But why is it more popular in some areas than others, and can it replace conventional cultivation techniques?
For centuries, farmers have plowed their fields before sowing crops, first with rudimentary equipment, then cattle-drawn tills, then using more sophisticated, motorized machinery. Until the late 1970s, tilling, which involves turning over the top layer of soil, was the accepted, standard practice for arable farmers.
No-till farming first gained traction in the US in the early 1980s, driven in part by a desire to conserve and boost soil quality. But the practice also offered labor and fuel cost savings. Around the same time, concerns over the environmental consequences of traditional cultivation methods first began to surface. Issues such as soil erosion, flooding, leaching of nitrates into nearby watercourses and the need to replenish organic matter back into the soil demanded fresh thinking from farmers.
“With tilling, you take a lot of organic content out of the soil”- Harry Smit, RaboResearch
The practice involves sowing seeds directly into untilled ground using specialist planting equipment. Remaining plant matter from the previous season’s crops, or crop residue, is often left on the field to decompose and protect the topsoil. Advantages over conventional farming techniques include better moisture retention in soil, higher biodiversity on the land and the potential for better yields.
No-till methods are popular in the US, Brazil and Australia, land-abundant regions characterized by larger-scale farms. Because of the moisture retention no-till farming provides, it is well-suited to dryer climates.
“No-till allows soil’s complex ecosystem to operate as intended”- John Cherry, Groundswell
From cultivation to restoration
No-till farming’s other main advantage over conventional cultivation is the beneficial effects it can have on soil quality.
“With tilling, you take out a lot of the organic content,” says Harry Smit, a Senior Analyst specializing in Farm Inputs at Rabobank. “That organic matter remains in the soil with no-till farming. Not only that, there is more biological activity from organisms such as insects and worms in non-tilled soil, which often means you don’t need as many fertilizers.”
No-till farmer John Cherry, who helps run the annual Groundswell soil regeneration conference in the UK, goes even further. “The act of plowing itself is catastrophic for soil at a biological level,” he says. “Soil is a dynamic ecosystem – almost a poor-man’s rainforest – and that gets damaged by the exposure to sun and rain caused by cultivation. By leaving the soil undisturbed, no-till allows that complex ecosystem to operate as intended.
“Also, with organic content and root pathways remaining intact, you don’t need as much input into the land such as fertilizers and sprays.”
Young corn plants in a no-till field.
Less energy, less carbon
It’s not just the soil that benefits from the approach; the broader environment does too.
“You’re using much less energy because you’re not fuelling a tractor to plow a field before sowing,” says Steve Nicholson, Vice-President, RaboResearch Food & Agribusiness. “There’s less compaction, which can help prevent flooding. And in recent years, no-till farms have employed ‘cover crops’ too, which not only add nutrients, they hold them in the soil as well.”
Other common no-till practices such as the planting of ‘buffer strips’ benefit the environment too, since they prevent soil that’s easily eroded from reaching nearby waterways and contaminating them with nitrates. But Cherry believes the widespread adoption of no-till has the potential to do much more.
“One of soil’s prime functions is to lock in carbon. And the more carbon in the soil, the better it is,” he says. “Around two thirds of the excess carbon in the atmosphere comes from soil that has been depleted by over-plowing and grazing. No-till can ultimately have the effect of removing excess carbon from the atmosphere.”
A plowed field in Devon, England. No-till farming is still a relatively niche practice in Europe.
Europe plows on
So with the potential to deliver higher yields, improve soil quality and help the environment, why isn’t no-till farming standard practice around the world? While enjoying uptake levels of more than 90 percent in the US and Australia, no-till farming is still a relatively niche practice in Europe, especially in the north of the continent.
For Cherry, the slow adoption rates in Europe are as much a result of attitudes as they are a response to the method’s perceived unsuitability in the region.
“The biggest barrier to no-till farming is between the ears,” he says. “People are obsessed with yields, often at the expense of profit, and seem unwilling to risk breaking away from traditional farming methods even though that might eventually lead to higher yields anyway.”
Cherry also cites a lack of enthusiasm among the farming community’s institutions for the slow uptake. “One of the problems is that there’s almost no interest in this method from universities and in government circles,” he says. “All the educational courses and farming subsidies are geared towards producing more and increasing profits for large corporations, not towards exploring new ways of getting more out with less input. Soil conservation really should be our government’s top priority in agriculture, but it’s not.
“No-till is becoming increasingly popular despite that, with more people beginning to see the benefits and struggling to maintain the returns they need to survive using high-input systems. But we need to get the government on board too and develop a system to incentivize these methods appropriately.”
“In Australia, it’s more uncommon not to be using no-till methods”- Wes Lefroy, RaboResearch
Best practices in Australia
The picture is different in Australia, where no-till has become accepted best practice since it was first adopted in the 1970s.
“In large part, no-till adoption was driven by the need to find solutions to the problems Western Australian farmers were experiencing with dryer, sandier soil, retaining organic matter in that soil and preventing soil erosion,” says Wes Lefroy, Agricultural Analyst at Rabobank in Sydney, Australia.
“Since then, strongly driven by farming associations and evidence from research, it’s become so incredibly popular, it’s now more uncommon not to be using no-till methods.”
From an Australian perspective, no-till allows greater efficiencies due to the generally larger size of the farms alongside cheaper labor costs. And having experienced higher yields, no-till farmers have seen no problems with scalability.
“Improved weed management strategies – in combination with better spraying technology – has also been a big enabler of no-till adoption,” adds Lefroy.
A no-till planter sows soybean seeds in the US. Photo: United Soybean Board
Future focus: precision planting
No-till farming is widely adopted in the US. According to Nicholson, it’s been common practice since the early 1980s and no-till or minimal till farming is present in every corner of the Corn Belt. He believes the practice is perfectly capable of satisfying the growing global demand for food.
For Nicholson, the emphasis now in the US is very much on improving the practice and refining the technology available to derive further benefits. “The future of no-till here in the US really is about advances in the planting technology field,” he explains. “In particular, precision planting technology that allows seeds to be planted in particular areas and fertilizers to be applied in the appropriate amounts based on the soil chemistry and plant needs. That is one of the next big things we’ll see.”
According to Nicholson, it’s not far off. Planting machinery has become ever more sophisticated – with some planters able to sow multiple seed varieties in the same row.
In Australia, optimization of the system is the next step, according to Lefroy. “There are so many different aspects in terms of the physical, chemical and biological components of the soil,” he explains. “How those three interact and the best practice techniques around that – that’s where we’re going to see continued gains in the no-till system.”
“Under the current system, some farms have 40 or 50 harvests left”- John Cherry, Groundswell
Lessons for the future of farming
For John Cherry, the potential of no-till in Europe is still to be realized. “More farmers are getting on board with the idea and have recognized the need to change in order to get results,” he says. “But not nearly enough. When you hear talk that some conventional farms only have between 40 and 50 harvests left in them using the current system, that’s frightening.
“That said, the lessons we can learn from the US, where things have improved dramatically thanks to new techniques, make me think the future for no-till farming is rosy.”