Farmers have tilled the soil - turning it as preparation for planting - for millennia. But that legacy is under scrutiny today as “soil health” has entered the vernacular – at least amongst people aware of prevailing agri-trends such as those recently discussed in the New York Times.
“I think part of the excitement is the catchiness of the new term,” said Tony Vyn, professor of agronomy at Purdue University. “Years ago, we called it soil quality and now it’s soil health. Part of it is also the growing concern for hypoxia (oxygen depletion) in the Gulf of Mexico and the phosphorous going into Lake Erie. This and increased societal scrutiny have advanced the notion that we need to increase our attention to soil health.”
No-till soil-conservation farming, aka “green manures,” follows nature in its natural cycle of regeneration. Proponents of no-till say over-tilling the soil leaves it exposed to erosion, particularly from water and wind. The Dust Bowl of the 1930s epitomized what severe windstorms and droughts, along with eroding topsoil, do to destroy crops, livelihoods and life itself.
No-till farming eschews use of machinery and maintains and reuses crop residue, which can provide as much as 2 inches of additional water to crops in late summer.
But vocal critics of no-till cite drawbacks such as the fact that root crops require tilled lands; and that switching farming methods is a huge expense, requires new equipment and, worst of all, uses chemical herbicides and pesticides.
The benefits of tillage include:
- Soil conditioning
- Weed and pest suppression
- Residue management
- Incorporation and mixing
- Land forming
- Stimulation of nutrient release
Negative effects of tillage include:
- Compaction of soil below the depth of tillage
- Crusting of soil when soil pulverization is followed by rain
- Increased susceptibility to water and wind erosion
- Accelerated decomposition of organic matter
- Cost of equipment purchase and operation
- Energy cost of tillage operations
- Labor and temporal obligations
Government surveys suggest that no-tillage farming now accounts for about 35 percent of cropland in the U.S.
Paul Jasa, extension engineer at the University of Nebraska-Lincoln, is a proponent of no-tillage. As Jasa pointed out, we were all organic farmers before 1950.
“Soil health disappeared from the radar screen when large scale farming really took over and farmers could buy technology and we didn’t have to worry about soil health,” he said. “We became lazy managers with the introduction of commercial fertilizers, pesticide to kill pests and herbicides to kill weeds. We ignored the importance of a healthy soil system and started doing it with technology instead.”
He likens issues of soil health to human health: “My doctor says my cholesterol is too high and I need to lose some weight. It’s a lot easier for me to take a cholesterol-lowering pill than it is to exercise and watch what I eat.”
No-Till on the Plains is a Kansas-based nonprofit devoted to educating growers about “agricultural production systems that model nature.” It sponsors professional trips for farmers and agricultural professionals and tours no-till farms such as the Kaup farm near Stuart, Neb., or the Tucker farm near Venango, Neb.
“It’s a massive paradigm shift,” said Ray Archuleta, agronomist at the Natural Resources Conservation Service, proponents of soil-conservation.
“Each 1 percent increase in soil organic matter helps soil hold 20,000 gallons more water per acre,” said Claire O’Connor, staff lawyer and agriculture specialist at the Natural Resources Defense Council.
Ohana No-Till Farm, near Meridian, Idaho, is in its second season of no-till farming, and as "grow maestro" David Mitchell recently reported: "It was a very unique set of circumstances that allowed us to start right from the get-go (as a no-till farm). We had a pretty good success rate our first season."
Mitchell said his yield is three times that of a traditional farm of the same size using no chemical herbicides. "This is probably the most sustainable method that can be done on a large scale. I would love to see more commercial farmers embrace the no-till method," he said.
Soil allows the ecosystem to grow food and store water for all life and agriculture. Its store of carbon, the largest on land, keeps a slight lid on climate warming. But as we continue to degrade our soil, the consequences are mounting. According to Paul West, co-director and lead scientist at the Global Landscapes Initiative: “Each year between 10 and 30 gigatons of soil is lost through erosion. To put that in context, all the concrete in the biggest structure on earth, the Three Gorges Dam, adds up to 0.07 gigatons.”
The largest think-tank of no-tillers in the nation will convene in Indianapolis in January. The list of companies exhibiting and sponsors includes:
• Koch Agronomic Services, manufacturers of Agrotain
• Equipment Technologies, manufacturers of Apache sprayers
• Agro-Culture Liquid Fertilizers
• Verdesian Life Sciences
• Case IH
• Titan International, manufacturers of Goodyear farm tires
• Ag Leader Technology
• Needham Ag Technologies
• Yetter Mfg. Co.
• Dawn Equipment
• KB Seed Solutions
• Kinze Mfg.
The jury is still out – but clearly the till versus no-till debate is gaining momentum in mainstream farming as a timely issue of utmost priority.