If you're thinking about switching to strip-till, learn all you can about the system and talk to other farmers who are already doing it, suggests Iowa State University Soil Scientist Mahdi Al-Kaisi. Then ask yourself the following questions, he says. If you decide to try it, he recommends to start small and be patient.
Is your current tillage system working for you?
Are you meeting your conservation goals?
Are you willing to make a long-term commitment to the new tillage system?
Are cold, wet soils limiting planting timeliness?
Are stands and early growth satisfactory?
Is soil compaction a problem?
Do you have the necessary labor to complete fall strip-tillage?
Are you willing to change your management practices and your fertility and pest-control programs?
Are you willing to invest in the necessary equipment?
Higher average returns than conventional or no-till systems, according to a Minnesota study.
Warmer, drier soil in the strip.
Improved germination and seedling growth in cold conditions, compared to no-till.
Ideal fertilizer placement, directly under seedlings.
Less compaction below the seedling.
Leaves up to two-thirds of residue cover undisturbed for good erosion control and lower moisture loss.
Fewer field passes than conventional tillage.
Uses less fuel, labor and machinery than conventional tillage.
Little benefit, compared to no-till, in warm springs or in warm, well-drained soils. Advantage limited to poorly drained, wet, cold soils where seed germination is delayed.
Needs more tractor power than a drill or no-till planter. It takes about 15-20 hp/row to pull a 12- or 16-row strip-till toolbar plus dry fertilizer cart or anhydrous nurse tanks.
Needs skillful fall tillage, so that corn rows can be accurately planted in the strips.
Risk of soil erosion in the strips. Not recommended for slopes over 7% without contouring or 10% with contouring, according to the Iowa State University Extension Service.
Narrow window for fall application of nitrogen fertilizer; cost of nitrogen inhibitor.
Potential weed shifts, insect problems and fertility issues.
Soil compaction between the tilled zones.
Strip-tillage saves nearly half of fragile soybean residue, according to a two-year on-farm tillage study by the Universityof Minnesota (U of M).
Chisel plowing removed an average of 80% of soybean residue cover, the study found, and in some fields, virtually all the soil was left uncovered. One-pass tillage preserved more residue cover than chisel plowing, averaging just under 30%. No-till saved an average residue cover of 60% and strip-till saved 47%, on average.
These results are similar to average residue accumulations during six years of small-plot tillage trials at the U of M, according to U of M Soil Scientist Jeff Vetsch.
However, residue cover varied widely among the 10 farm research sites, even within tillage systems, says Minnesota Extension Regional Educataor Jodi DeJong-Hughes, who led the on-farm trials. One-pass spring cultivation, for example, left from 11% to 54% residue cover. Similarly, strip-till residue cover ranged from 21% to 69%. “The range has to do with the previous year's tillage treatment plus the type of tillage equipment used,” she says.
The Natural Resources Conservation Service standards for conservation tillage require 30% residue cover. The goal of strip-till is less than 10% residue cover on the strips and full residue cover between the rows, DeJong-Hughes says.