At first glance, the concept of no-till farming seems a quaint relic of the past, a footnote in a history book, perhaps. Farmers in California’s central farmlands have been using large disks and tills to rip and turn their soil for almost a century. But no-till could have substantial human health benefits for Central Valley residents, as well as financial gains for farmers, according to some agricultural experts at UC Davis and across the country. According to experts, the potential positive results of no-till farming include water conservation, maximizing soil health, decreasing equipment costs and reducing the sometimes dangerously high dust levels in the San Joaquin and Sacramento valleys.
No-till farming, which is sometimes called zero tillage, is very much what it sounds like — a method of farming without disrupting the soil. Tilling, which is used to create irrigation furrows and reduce weeds, digs up from 4 inches to a foot of soil. Since most of California’s 156,000 square miles of agricultural fields are tilled when dry, dust can be a significant by-product. The California Air Resources Control Board has publicly stated that: “The dust pollution problem in California is widespread and severe. People in California are exposed to more unhealthful levels of PM10 (dust particulates 10 microns or smaller) than any other air pollutant.”
Although most countries and more than 35 percent of America’s farmlands are using no-till, California lags far behind with only 3-percent utilization, according to Dr. Jeffrey Mitchell, a cropping system specialist and no-till expert at UC Davis. Lack of knowledge and a reluctance to change management techniques are two key reasons, says Mitchell.
However, for area farmers like Yolo County’s Fritz Durst, who has been using the no-till method for 20 years, the benefits have been many and may include substantially increased crop production. ”We started in 1985 using the no-till method, and since then we’ve doubled our yield potential,” says Durst, whose farm is on the western edge of the Sacramento Valley.
Michael Crowley, who has used the no-till method on 400 acres just west of Fairfield and another 270 acres near Turlock for about 10 years, agrees. “I not only get great production, I save a great deal by not buying expensive tilling equipment, and I look to double my production in times of little rainfall because no-till increases the water-storing capacity of the soil,” Crowley says. “At the same time, the dust reduction is incredible. When the wind blows, I collect dirt from my neighbors who use tillage, but they don’t get any of mine.”
For those crops that lend themselves to no-till farming, savings average about $50 an acre. “There are tremendous opportunities for farmers in no-till,” says Mitchell. “These include soil function and health and increased water, nitrogen and carbon storage.”
One of the leading proponents of no-till in the San Joaquin Valley is Jesse Sanchez, who manages a 4,000-acre farm south of Modesto. “We definitely save money through higher production, less water usage and lowered equipment and fuel costs,” says Sanchez, who was recently asked to the White House to talk to President Obama’s advisors on the practice. “We’ve been doing it for 10 years. I can see a significant improvement in the quality of the soil over that time. There are so many ways it benefits us. For example, before we went to no-till, we used about 13 gallons of diesel in our equipment per acre, now we use about three.”
According to Mitchell, tilling came into fashion in California in the 1930s — ironically, about the same time tillage methods were being blamed for the Dust Bowl in the Midwest — when irrigated farming began in the valleys. It was used extensively until the 1990s, when farmers in the U.S. and worldwide began re-discovering the benefits of no-till. Battling weeds is still an issue with no-till, as it is with farms under tillage, but researchers are working on developing weed-free cover crops.
Despite California’s reputation as a leader in agricultural innovation and the fact that most countries worldwide utilize no-till, California has been slow to try it. “It’s largely a matter of our farmers not being familiar with no-till practices,” Mitchell says. “At the same time, though, there is a risk-management element involved. The systems developed here 80 years ago were phenomenally successful for area farmers and because they worked so well, and were so profitable, nobody has felt they should make a change.”
Randy Southward, a soil scientist and colleague of Mitchell’s at UC Davis, agrees. “I think California farmers may not yet realize the immediate benefits of no-till,” he says. “Those include using less fuel, an increased yield and measurable water savings.” In addition, scientific studies have indicated that a few major crops, like cotton, may not reap major benefits from no-till, although Sanchez disagrees. He found savings with cotton and many other crops.
“There are tremendous opportunities for farmers in no-till. These include soil function and health and increased water, nitrogen and carbon storage.” Dr. Jeffrey Mitchell, crop system specialist and no-till expert, UC Davis
Most of the focus on no-till has been on its agricultural applications, but the substantial reduction in air pollution may ultimately emerge as a key factor in its acceptance. A 2013 study done by Massachusetts Institute of Technology researchers found that more than 130,000 Californians die prematurely each year from air pollution. Bakersfield, Merced and Fresno topped the American Lung Association’s list of American cities with the most persistent air pollution in 2013. Schools in Fresno sometimes fly color-coded flags to tell students whether it is healthy to play outside, depending on the air quality. Some of this comes from automobile and other pollutants blown in from coastal cities, but a substantial amount of the problem is the dust.
“Like most no-till farmers, I only plant when the soil is moist, but those using tillage can’t open their soil when it’s wet because it will compact,” says Crowley. “That’s why they tear open the soil when it’s dry. That’s where the dust comes from.”
The recent drought has spurred some interest in no-till, and many experts say there is a role for the California State Legislature to play in building on that interest. Supporters say financial incentives such as tax credits could help focus positive attention on the process. A surprising possible benefit of no-till is that many experts believe that carbon, which is associated with greenhouse gases and global warming, is more likely to remain sequestered in the soil when it is not disturbed by tillage. Although some researchers have questioned this, most believe this sequestering does occur and therefore no-till farmers would be eligible for tax credits available for those who help reduce carbon emissions.
It’s important to know that there are some differences of opinion among experts in terms of the yield created by no-till. While reports indicate that no-till is especially adaptable to dry-land conditions where farmers rely on rainfall rather than irrigation, an international team led by UC Davis researchers found that worldwide, no-till may not always result in the overall “sustainable intensification of agriculture.” Yet, the same report states that several opportunities still exist for the no-till method to match or even exceed conventional tillage methods.
“I think part of the problem is it took me three years after switching to no-till to see all the benefits,” says Crowley. “It takes that long for the damage to the soil from tilling to heal. Soil doesn’t automatically restructure itself. I’m not saying you won’t have decent crop production during that time, but a lot of farmers get fearful and turn back before the big advantages kick in. I think a lot of researchers may not realize this when they compare no-till to tilled production.”
Mitchell summarized the most obvious benefits. “Since water does not evaporate as quickly in no-till fields, savings in water cost are easy to determine,” he says. “In addition, fewer pesticides are often needed and farmers also save money by the diminished need to buy the expensive tilling equipment and to pay people to run them.” He adds that soil in the fields, no longer exposed by the tilling, remains richer in its biodiversity and can sustain higher yields. Compaction of the soils, caused by the heavy tilling equipment, is also lessened.
Because the soil is not disturbed in no-till, the soil biota is left in its natural state and is more erosion- and pest-resistant than tilled soil. Underground creatures such as worms, which are crucial to good soil health, thrive in no-till conditions, while tillage can radically change underground ecosystems. “Turning the soil over puts all the good organisms, which like air, down where they can’t get it — and the ones that don’t like air up on the surface,” says Crowley. “You destroy the homes of the soil organisms that create healthy crops. Why mess with their lifestyle?”
Although proponents like Mitchell and Sanchez are optimistic about the future spread of no-till conservation methods in California, there is little evidence to show the state is moving to catch up with the rest of the nation and world. Farmers, many of whom are still paying for expensive tillage equipment, are slow to change and government officials, despite the potential dust reduction and subsequent human and soil health benefits of no-till, have not moved to create incentives. Those farmers who are already utilizing the process, though, are convinced.
“Whether California wakes up and realizes what no-till offers — and I hope it does — I’ll just continue to enjoy all its advantages,” says Crowley. “I tell everybody who wants to listen that it works.”
Michael Bowker is the incoming executive editor for Comstock’s magazine.