As we enter the new millennium, no-till's overall numbers have never been better. But that hasn't always been the case.
For years, the soil-saving advantage was touted. Then folks talked about its boosts to water quality. But on the downside, the system sometimes led to poor stands and slow growth on early planted corn. That may all be changing now.
Consider the latest benefit enthusiasts - and researchers - are touting: No-till actually helps reduce greenhouse gases and global warming.
USDA scientists have recently found that considerable amounts of carbon dioxide are released into the atmosphere when soil is tilled. Following this logic, no-till releases the smallest amount of carbon dioxide. That carbon remains in the soil to build organic matter and long-term productivity.
The profit push
Behind no-till's growth are big strides in machinery and herbicide developments. And producers have improved their management skills needed for no-till. These factors add up to perhaps the most important motivator - profitability.
And the news is good. Two recent major multiyear studies show that, profit-wise, no-till for soybeans equals or tops conventional systems.
An eight-state Midwestern study found that no-till was competitive in all states and, overall, slightly more profitable than full-width tillage systems. And in a six-year Indiana program, the average per-acre costs for producing soybeans were lowest for no-till, followed by ridge-till, reduced-till and plow tillage, respectively.
No-till acreage is growing steadily, especially for soybeans. No-till now claims 32% of soybean acres nationally. Strip-till, to some a modified form of straight no-till, is growing for corn, especially in more Northern production areas.
The advantages of conservation tillage have recently been quantified, and the list is impressive indeed, as provided by the Conservation Technology Information Center:
* Reduced labor requirement. No-till requires as little as one trip for planting, compared to two or more tillage operations, plus planting, for conventional tillage.
*Time savings. On a 500-acre farm, the time savings can be as great as 225 hours - or almost four 60-hour work weeks.
* Reduced machinery wear. Fewer trips save an estimated $5/acre on machinery wear and maintenance costs. That's a $2,500 savings on a 500-acre farm.
* Fuel savings. On average, 3.5 gallons/acre of fuel can be saved compared with conventional tillage systems.
* Improved long-term productivity. The less you till, the more carbon you retain in the soil to build organic matter and promote future productivity.
* Improved surface water quality. Crop residues help hold soil particles and associated nutrients and pesticides on a field. On some sites, conservation tillage can cut herbicide runoff rates in half, thus protecting stream and lake water quality.
* Reduced soil erosion. Crop residues on the soil surface cut erosion by water and wind. Depending on the amount of residues on a field, soil erosion can be reduced by up to 90% compared to an unprotected, intensively tilled field.
* Higher soil moisture. Because crop residues reduce water evaporation from the top few inches of soil, no-till can make as much as two additional inches of water available for growing plants in late summer.
* Improved water infiltration. Crop residues act as mini dams to slow water runoff, allowing water more time to soak into the soil. Also, infiltration is increased by channels, or macropores, created by earthworms and old plant roots that are left intact with no-till.
* Decreased soil compaction. Reduced weight and horsepower requirements with no-till can help minimize compaction.
* Improved soil tilth. No-till increases soil particle aggregation (small soil clumps), which makes it easier for water to move through the soil and allows plants to use less energy to establish roots.
* More wildlife. Crop residues provide shelter and food for wildlife, especially game birds and small animals.
* Reduced air pollution. Crop residues reduce wind erosion and the amount of dust in the air. Also, fewer field trips reduce fossil fuel emissions.