Early Season Weed Control with Pre-emergence Herbicides

A man and woman squatting in a field

Start Strong to End Strong

When it comes to strong soybean yields, how you handle the early season significantly impacts your success at harvest. But it’s not just about controlling early season weeds. It’s about ensuring that you have a plan in place to keep your soybean fields clean through canopy closure, which has one of the biggest impacts on yield.


Early season pressure from pigweed and other tough weeds means soybeans are competing for light, moisture and nutrients right out of the gate, with yield taking a hit. In fact, a study from the University of Nebraska shows that a two-week delay in planting can impact soybean yields up to 8.82 bushels per acre.2 Early planting gives soybeans an advantage in capturing light and moisture, increasing vegetative growth and reaching canopy earlier, which equals a competitive advantage over weeds.


Incorporating a pre-emergence herbicide with residual as the foundation of a comprehensive weed control program can make the difference on many different fronts including:

  • Managing yield loss due to early season competition.  
  • Reducing pressure on post-emergent herbicides.
  • Giving soybeans a wider window to grow and establish without competition.
  • Allowing for the introduction of a different site(s) of action to fight weed resistance.  


Why would you be interested reducing the pressure on post-emergence herbicides? Because weed resistance is only becoming a bigger challenge for soybean farmers. Relying on a single post-emergent herbicide application is no longer sustainable or successful in long term prevention of resistant weeds. Managing resistance relies on a comprehensive program, and by starting with a foundational pre-emergent herbicide with residual you reduce early-season weed pressure. This results in more consistent post-emergent herbicide coverage as well as an extended application window. 

The Pre-Emerge Solution

A pre-emergence herbicide with a long-lasting residual is the key for success in the current season, as well as the long-term fight against weed resistance. But how do you choose the right product? There are several criteria that you can use to ensure that they are getting the right product for their field.


  • Spectrum of control

First, the herbicide must kill the weeds. A foundational pre-emergence residual herbicide like Zidua® PRO herbicide from BASF provides broad-spectrum control, with up to three- to five-times faster burndown than 2,4-D ester or glyphosate alone on tough broadleaf weeds.3


  • Sites of action

Relying on a single site of action doesn’t deliver the needed early season performance or resistance management needed. Zidua PRO herbicide has three sites of action that provide built-in resistance management that reduces early-season weed pressure. That means more consistent post-emergent herbicide coverage, an extended application window and reduced selection pressure. A benefit that other pre-emergent products like the Authority® herbicide brands can’t match.


  • Length of residual

With up to two-weeks longer residual than many competitive products, Zidua PRO herbicide keeps soybean fields cleaner longer, regardless of trait platform.4 Longer residual control is possible because Zidua PRO herbicide is degraded by sunlight at a much slower rate than the competition, lasting more than 270 days longer on the surface before it begins to break down. 5,6,7


This means Zidua PRO herbicide provides longer-lasting residual control for some of the toughest weeds, like pigweed. Keeping fields clean through establishment and beyond not only helps soybeans achieve full yield potential, but also reduces the selection pressure on post-emergence herbicides.


  • Application timing

Zidua PRO herbicide has no soybean-planting interval in most soils. Meaning you can often plant and spray in the same day.


  • Trait Flexibility

When it comes to the different trait systems, Zidua PRO herbicide is the right pre-emergence solution for all soybean systems and tillage practices. When adopting Zidua PRO herbicide the only thing you have to lose is tough early season weeds.


There are a lot of pre-emergent herbicides available to you for your soybean fields. Zidua PRO herbicide offers a combination of proven control, longer-lasting residual, application flexibility and trait independence providing a strong foundation for any weed control program. Focus on maximizing yields this season and managing the impact of resistant weeds in the future. 

1 Werle, R., Conley, S. 2018. Are you PRE-emergence ready for soybean planting? Wisconsin Weed Science. University of Wisconsin – Madison. Website: https://www.wiscweeds.info/post/are-you-pre-emergence-ready-for-soybean-planting. Accessed September 13, 2021.

2 Spect, J.E., G.L. Zoubek, B.S. VanDeWalle, D.L. Varner. 2012. Soybean planting date – When and why. University of Nebraska Extension Publication EC145. Website: https://extensionpublications.unl.edu/assets/pdf/ec145.pdf. Accessed January 18, 2022.

3 Internal BASF Trials.

4 BASF sponsored studies conducted nationally in 2015 and 2016.

5 Dimou et al. 2002 https://www.tandfonline.com/doi/abs/10.1080/0306731031000149660

6 Shaner, D.L. (2014) Herbicide Handbook. 10th Edition, Weed Science Society of America, Champaign, 513 p. 

7 Health Canada Pest Management Regulatory Agency, 2012. Proposed Registration Decision,Pyroxasulfone,PRD2012-20. http://www.publications.gc.ca/collections/collection_2012/sc-hc/H113-9-2012-20-eng.pdf


 Always read and follow label directions. Zidua® is a registered trademark of BASF. Authority® is a registered trademark of FMC Corporation. Sonic® is a registered trademark of Corteva Agriscience. ©2022 BASF Corporation. All rights reserved.