1. Soil incorporation.

    Incorporation will reduce runoff losses by approximately 67 percent compared to surface application without incorporation. Atrazine (or atrazine tank mix products) can be incorporated into the top two inches of soil with a field cultivator, tandem disc or other implement.

    Benefit: Less atrazine is present at the soil surface, where it is most vulnerable to runoff. A good option for producers who use tillage prior to planting.

  2. Application timing.

    The potential runoff of atrazine can be decreased by 50 percent by applying atrazine prior to April 15 compared to applications in May and June, when rainfall intensity peaks. Early-applied atrazine is more likely to get moved down into the soil by gentle rains of early spring than swept off the field by runoff water during intense late spring and early summer storms.

    Benefit: Helps reduce runoff potential on no-till or reduced-till fields where soil applications of atrazine are used.

  3. Split applications.

    Applying atrazine and tank mixes as split applications has the potential to reduce atrazine runoff by 25 to 33 percent compared to applying all the product at planting time. Examples include applying half to two-thirds in March and the remainder just prior to or immediately following planting.

    Benefit: Reduces the amount of atrazine on the surface during periods of higher rainfall intensities.

  4. Reduce soil-applied rates.

    Formulations with low atrazine content can still provide excellent control of pigweed and other small-seeded broadleaf weeds while reducing the amount of atrazine applied by as much as 33 percent.

    Benefit: Maintains good weed control of small-seeded broadleaf weeds while reducing atrazine rates.

  5. Postemergence applications of atrazine.

    Postemergence mixtures contain very low rates of atrazine yet provide excellent broadleaf weed control. Using postemergence mixtures results in 67 percent less atrazine runoff compared to typical preemergence soil-applied atrazine applications.

    Benefit: By reducing the amount of atrazine applied to the soil, runoff potential is reduced.

  6. Combine surface applications with postemergence atrazine.

    Applying reduced soil-applied rates of approximately one pound active ingredient of atrazine per acre at the time followed, if necessary, by a postemergence atrazine application can reduce atrazine runoff by 25 percent compared to applying all at planting time. This two-step program often provides the best control of velvetleaf, cocklebur and other tough broadleaf weeds.

    Benefit: Flexible option. Can maintain excellent weed control while reducing runoff potential.

  7. Alternative herbicides or non-chemical weed control methods.

    New herbicides containing no atrazine are now available. Using these herbicides reduces atrazine runoff by 100 percent. However, some of these herbicides do not control ALS-resistant weeds. The use of crop rotations, cultivation and other non-chemical weed control methods may reduce or eliminate the need for herbicides.

    Benefit: Can remove atrazine from the picture entirely if alternative herbicides provide sufficient control or if non-chemical weed control methods alone are sufficient.

  8. Vegetative filter strips.

    Vegetative filter strips that reduce water flow rate from the field can reduce atrazine loss up to 25 percent. Removal of atrazine from runoff water by filter strips is directly proportional to the amount of runoff water that soaks down into the filter strip.

    Benefit: Can reduce atrazine loss without affecting weed control effectiveness or cost.

  9. Band applications.

    Banding atrazine over the row at planting or during cultivation reduces the total amount applied on a field by 50 to 67 percent. As a result, less atrazine is available for possible runoff than when the herbicide is broadcast over the entire field.

    Benefit: Cultivation between the rows is a good way to reduce atrazine use and still get good control.

  10. Buffer zones.

    Avoid atrazine applications near water supplies and environmentally sensitive areas.

    Benefit: Can reduce atrazine loss without affecting weed control effectiveness or cost.


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