Tips to determine the why, when and how you till
As farmers gather the bounty of one crop their minds are thinking about the next one. For some, that starts with a tillage game plan.
“I would first ask: Why do I need tillage? And why do fall tillage rather than spring tillage?” says Charles Wortmann, University of Nebraska Extension soil specialist.
Deciding the best time to till depends on several factors—some of which are outside your control. Soil type and heath, manure and/or fertilizer applications and weed control also need to be taken into consideration.
In some states wet weather and subsequently slow harvest might mean there isn’t enough time to run a tillage tool in the fall, even if that’s your typical schedule. When this happens, prioritize which fields will benefit the most from fall tillage versus those that can wait until spring:
1. Soils that need more aeration or deep tillage to break up compaction are better suited for fall tillage, Wortmann says. If you’re planning more shallow tillage, waiting until the spring can help reduce the amount of potential soil loss from erosion by maintaining cover longer.
You can determine a field’s risk of soil loss with the help of a local Natural Resources Conservation Services agent. The revised universal soil loss equation can be used to estimate annual loss based on soil type, slope, rainfall and other management.
“Some soil loss is less than 2 tons per year for crop land, but other fields might average soil loss to erosion at 15 tons per year,” Wortmann, explains. “Any soil loss is of concern but situations with an average loss of more than 5 tons per year definitely should have a change of management.”
Keep in mind fall tillage also leaves soil exposed all winter and spring and lighter soils with more sand are likely to suffer wind erosion. All soil types can develop large ruts from water movement. Leaving a layer of residue could help mitigate loss of soil quantity and quality.
“We need a residue blanket to intersect rain,” says Paul Gross, Michigan State University field crops educator. “If we don’t have a good cover, beating rain can make the soil crust.”
Crusting is tricky in the spring. Water won’t infiltrate and seedlings could struggle to break through the crust during emergence. Consider challenges associated with excess rain such as compaction and crusting before tilling this fall.
2. Some states have specific requirements for manure, which means you might have no choice but to till shortly after it’s applied in the fall.
“It’s a big challenge this year, it’s been really wet and we might cause more problems like compaction, which requires additional tillage,” Gross says. “But from a compliance standpoint the manure has to be worked in.”
3. Finally there are those pesky weeds and resistance issues to consider. If you’re plagued by early season weeds, even with pre-emergent herbicide, you might be able to gain more control with tillage. Moving seeds deeper into the soil profile greatly reduces the sunlight they receive and the likelihood they can germinate.
Take a critical look at timing, the needs of each field, compliance issues and weed control options when planning your tillage pass.