By Brian Hefty

Now that many of our old standard corn herbicides are off-patent, the market seems flooded with generic alternatives, premixes, and a bunch of names that may sound similar but have different active ingredients and use rates. I work with these products every day, and even I get confused sometimes!

Below are my top 3 situational choices for corn pre-emerge herbicides. My biggest advice for you is to make sure you know exactly what you are getting and that whatever it is, you get fantastic weed control. If you don’t, either your use rate isn’t high enough or you need to switch products because there are a lot of great pre-emerge herbicides out there.

  1. Conventional Corn. If you have conventional corn, you don’t have any cheap, post-emerge grass option, but your post-emerge broadleaf options are still awesome. Therefore, we encourage you to use a full rate of a GRASS killer pre. In other words, pick any Group 15: Harness, Surpass, Outlook, Dual, or Zidua. Again, use a full rate – don’t skimp. If you don’t kill pretty much all the grass pre-emerge you’ll have to come back later with Accent, and that is marginal, at best.
  2. Roundup Corn with Resistant Broadleaves. While you can use a Group 15, we would probably suggest running with Verdict (Outlook plus Sharpen), Resicore (Surpass plus Callisto plus Stinger), or Acuron Flexi (Dual plus Callisto plus bicyclopyrone) instead. These products all have a cut rate of Group 15, but they have residual broadleaf herbicides so you get more activity on those tough, resistant weeds.
  3. Cheapest Resistant Broadleaf Option. Once again this year, it’s probably SureStart or TripleFLEX. I love the fact these premixes contain Surpass and Stinger, but I don’t like the Python in there, since it is an ALS herbicide. In other words, on your ALS-resistant weeds, Python won’t work. However, Python does have activity on several weeds that Roundup struggles with, including velvetleaf, lambsquarters, several winter annuals, and more. You could also run with Balance Flexx herbicide, which is a straight HPPD. While inexpensive and good on many broadleaves, it is fairly weak on grass.


Don’t double up on HPPD chemistry this season!! In other words, if you want to use a mesotrione (Callisto) product or any other HPPD post-emerge, absolutely do not use an HPPD pre. We are very worried about carryover and weed resistance. Use an HPPD once per season only, either pre or post!