Be prepared to terminate your cover crops in 2025

By now you know how the 4Rs of nutrient management help optimize fertilizer use. The same principles—Right source, Right rate, Right time, and Right place—can also guide you in effective cover crop termination.

Right source: Choose the right chemistry for termination and weed management

Selecting the appropriate tank mix is critical for effective termination. Make sure that you consider the below when making your decision:

• What is your cover crop type?
  • Grasses like cereal rye require a full label rate of glyphosate, while broadleaf covers like clover or vetch may need an added growth regulator like 2,4-D.
• What is your next cover crop or cash crop being planted?

  • Consider any rotational restrictions before selecting herbicides to avoid carryover issues.

• Do you struggle with the presence of herbicide resistant weeds?

  • Pre-emergence: Pair the cover crop termination program with other control methods (i.e., 5 oz Authority^® First + 24 oz metolachlor) to improve early-season control.

  • Post-emergence: Use multiple modes of action. Combining glyphosate and 2,4-D with a broadleaf herbicide like Liberty^® or Sharpen^® in a post-emergence herbicide application can improve control.

• How do you intend to optimize herbicide performance?

  • Water conditioning: Use AMS (with glyphosate) or another conditioner to improve herbicide uptake and translocation.

    Adjuvants: Check the herbicide label for surfactants needed to improve retention.

For specific herbicide recommendations, restrictions, and more information, refer to:

Successful Cover Crop Termination with Herbicides

Termination with Herbicides | Southern Cover Crops Council

Waterhemp Control in 2025

Right rate: Maximize effectiveness

Always follow the label. Applying the full label rate prevents regrowth and ensures complete termination. Cutting corners or rates can lead to cover crops becoming a problem rather than a benefit.

Right time: Time for success

Timing depends largely on your specific management goals:

• Early termination (10-14 Days before planting):

Preserves soil moisture and prevents planting delays.

• Late termination (at planting or planting green):

Maximizes biomass for weed suppression, organic matter, and moisture retention.

• Weather conditions:

Herbicides work best when daytime temperatures are above 55°F and nighttime temperatures are above 40°F for at least three consecutive days before application.

Other Considerations:

• Crop insurance:

Comply with your crop insurance company to ensure your plans for termination do not make you ineligible for programs.

For more details, see:

NRCS Cover Crop Termination Guidelines Version 4 (2019)

Cover Crop Termination Guidelines Revised for Crop Insurance | CropWatch | Nebraska

Right place: Cover crop termination in the context of soil health goals

Termination is one step in an integrated system. Some questions to ask yourself:

• Residue management
  • How will termination impact soil cover and microbial decomposition?
• Nutrient cycling
  • Will decomposing biomass temporarily tie up early season nutrients like nitrogen?
• Field conditions
  • Avoid spraying in waterlogged, high-wind, or cool conditions.

With a well-planned approach to termination, your cover crops can be a valuable tool in supporting soil health, managing weeds, and improving farm productivity. For a more personalized strategy, reach out to your Cargill Agronomist.

Below are a few other articles that can help you in building your cover crop termination strategy:

Best practices for terminating your cover crops this spring | CargillAg

Nail down your perfect termination timing | CargillAg

^{Sharpen® and Liberty® are registered trademarks of BASF Corporation. Authority® is a registered trademark of FMC corporation or an affiliate.}