COLUMBUS, Ohio -- The most ideal solution to production problems associated with a wet harvest is to practice continuous no-till, with the added benefit of adopting controlled traffic.
Randall Reeder, an Ohio State University Extension agricultural engineer, said that the farmers who better escaped the headaches of harvesting during this year's record-setting wet season were those who practice continuous no-till.
"Farmers with continuous no-till fields told me they had far less rutting than in fields tilled last fall. They still had some problems with wet soils, but not as bad as on tilled ground," said Reeder, who also holds a partial research appointment with the Ohio Agricultural Research and Development Center.
Compaction problems are most aggravated by tire ruts left in fields during harvest. Often, the deeper the rut, the deeper the soil compaction, which can have a tremendous impact on spring planting and an even greater impact on crop performance that doesn't become evident until later in the growing season. To make matters worse, the effects of compaction can last for years on some soils, costing growers up to 10 percent of their yield each year.
Practicing no-till is one solution to minimizing compaction and its effects. No-till is a conservation production practice characterized by planting, maintaining and harvesting a crop without disturbing the soil. Leaving the crop residue on the surface creates an ideal condition for earthworms and other soil organisms, reduces erosion, increases organic matter, and creates a soil structure with better drainage and root growth.
"For good soil structure, the key to the success with no-till is that it's practiced year after year," said Reeder. "No-tilling soybeans every other year doesn't count, and by tilling every other year for corn you lose most of the soil structure advantages of continuous no-till."
Add controlled traffic to a continuous no-till system and farmers could suffer fewer complications from compaction, said Reeder.
Controlled traffic is a method to manage soil compaction, whereby all farm equipment is the same width so that traffic is confined to specific paths year after year, and the remainder of the soil is untouched. Controlled traffic is usually matched with conservation tillage systems, like no-till or strip-till.
"The aim of controlled traffic is to minimize the amount of soil that gets driven on, eliminating compaction where plant roots are growing," said Reeder. "The average grain farmer will drive on three-fourths of the field in a two-year period. With controlled traffic, anywhere from 50 percent to 80 percent of the field never gets driven on and that includes 100 percent of the soil under corn rows."
Reeder said that controlled traffic works, but not enough farmers make use of the technology due to the time and cost to transition to the system.
"The good news is that precision agriculture technology, specifically auto-steer systems, makes it easier to adopt controlled traffic," said Reeder. "Controlled traffic without such a system requires the farmer to follow the tracks visually. But with an auto-steer system, with RTK (real-time kinetic) for example, the technology keeps the equipment aligned within an inch of right where the farmer needs to be in the field."
The following are some general tips farmers can follow when making the transition to a controlled traffic system. Reeder said some adjustments might be harder to make than others:
• Decide on the basic width. For most farmers, the decision is based on the size of the corn head. For example, if a farmer has a six-row corn head (15 feet), then the farmer will likely want a 30-foot planter, a 60-or 90-foot sprayer and a 30-foot drill.
• For equipment that does not fit the basic width, trade for new equipment that does match over the next few years.
• Select a grain platform the same width as the corn head on combines. Grain platforms are typically wider than the corn head in order to use the combine to its full capacity when harvesting different crops. There will be some loss of efficiency harvesting soybeans and small grains. "If the grain platform is the only machine that does not match, remember that there will be only one pass every two years so don't let that stop you from using controlled traffic for all other operations," said Reeder.
• Buy a drill the same width as the planter. Reeder said many drills are not as wide as the planter because farmers generally perceive timeliness of planting more important for corn than for soybeans.
• Choose a combine with tires that match the row spacing so that one is driving on the least amount of soil. Use split duals or, possibly, tall single tires. For no-till or mulch-till systems, tire width can be four inches less than row width. In ridge-till, the maximum recommended tire width is eight inches less than the row width.
• Fertilizer applicators must also match the width, or a multiple of it.
• Match grain cart tire spacings with the combine and run the cart in the same tracks as the previous pass of the combine.
"An important thing to remember is don't go overboard on expenditures that won't help at all in a fairly normal year," said Reeder. "The extremely wet weather we experienced in the fall of 2006 is rare, maybe happening once every 50 years."
Ohio has 3.7 million acres of no-till, or 41 percent of all cropland. Two-thirds of Ohio's soybean crop and 20 percent of the corn crop are planted into no-till. Of that total, Reeder estimates 10 percent to 20 percent of Ohio's cropland is in continuous no-till.
Adopting controlled traffic would improve yields and increase net profit for no-till farmers. And it will help every year, not just in the extreme wet ones.