Learning from the past can aid in future weed management plans and decisions.  Take the time to consider how the execution of your weed management plan could be improved next year to get one step closer to weed eradication.

Weed management is no easy task; it takes careful planning and discussions with trusted advisors like professional crop scouts, ag retail experts, and crop protection representatives.

Consider these three questions to prepare and plan for next year.

1.     How did weather impact my herbicide management plan?

While weather can’t be controlled, knowing how weather impacts your herbicide management plan can help you adjust. Weather can impact the effectiveness of an herbicide application. For example, an excessively wet spring can delay burndown, and, if a herbicide has been applied, there’s also the potential for leaching. According to the University of Illinois, a 2.5-inch rainfall can cause soil-applied herbicides to leach by 50% and up to 2.5 inches in depth. At this depth, the herbicide is below the weed seed germination zone, which can lead to weed escapes.

Cold spring temperature — in May, for example — can impact postemergence herbicide performance. Average daily temperatures that dip and remain below 50 degrees can add to crop stress, and weeds may not be able to metabolize the herbicide.

Herbicides can also be challenged in hot and dry conditions because many weed species develop thicker leaf cuticles that act as barriers to herbicide absorption. Add an adjuvant to help enhance herbicide effectiveness in these conditions. Read the label to understand any restrictions.

Keep a close eye on the forecast to help with herbicide efficacy.

• Soil-applied herbicides need rainfall for activation; make an application with moisture in the forecast, but avoid applying if substantial rainfall is predicted.
• In drought conditions, make applications in the morning while weeds are still perky from cooler overnight temperatures.
• Try to make post-herbicide applications when daytime temperatures are at least 60 degrees.

2.     Was the needed level of weed control achieved? 

If the answer is no, let’s explore why.

• Was it an herbicide-timing issue due to weather?
• Did you wait too long to spray and weed size became an issue?
• Did you have a full program approach to managing this season’s weeds (preemergence and postemergence applications)?
• Were you layering in residual herbicides as part of your herbicide program?
• Did you incorporate multiple modes of action?

3.     Are there management approaches that should be considered for next year?

If you continually saw weed escapes throughout the growing season, it might be time to consider additional management approaches to weed control, whether they are agronomic, cultural or preventative weed management tactics.

For example, consider cultivating fields, utilizing narrower row spacing when planting next or cover crops for weed suppression. According to Clemson University, cover crops can inhibit weed germination and reduce shoot dry weights for up to six weeks. An article stated (read here):

• Cereal rye reduces the germination of weeds for up to 6 weeks.
• Cover crop residue helps to reduce weed biomass, which has translated into less herbicide needed compared to a conventionally tilled system.
• Cover crops can reduce populations of Palmer amaranth when used as a part of a IPM approach.              

There are many weed control options to explore and research available to review. We encourage you to experiment and be innovative on your farm to address your weed issues.

For more information on recommendations for effective weed control options, talk to your local retailer or BASF representative and visit operationweederadication.com.