By Brian Hefty

When I was a young agronomist more than 25 years ago, almost every farmer I worked with was using Banvel, the dimethylamine salt of dicamba.  However, these farmers would constantly complain about 2 things: drift and crop injury.  If you have fear about drift or crop injury, let me put your fears to rest about the new Xtendimax and Engenia and Xtend Soybeans and Xtend Cotton.

Drift

There are 2 types of drift that we often discuss: physical drift and volatility.  With physical drift, you will always have to make sure the wind is in the right direction when spraying.  If you can see your product blowing into the neighbor’s sensitive crop, that’s obviously a problem.  The labels for Xtendimax and Engenia have buffer requirements, meaning you have to stay a certain number of feet away from a downwind, sensitive crop, which is only common sense.  When it comes to volatility, this is something out of your control.  If you spray a product on a plant, and it picks up and moves after that point, that’s volatility.  The old Banvel, and even Clarity to some degree, were notorious for this.  While Clarity may have reduced volatility by 90% vs. Banvel, they say that Xtendimax and Engenia reduce volatility by about 90% vs. Clarity.  That’s a huge upgrade.

Crop Injury

Thanks to the Xtend trait, dicamba can be safely applied at the same rate in Xtend soybeans and cotton as in most corn fields – 22 ounces of Xtendimax per acre.  In fact, you will find that dicamba is now safer on Xtend soybeans and Xtend cotton than it is in corn fields!  The evidence of that is you can apply 2 full shots of Xtendimax in Xtend soybeans and even more in Xtend cotton.  Would you ever even think about spraying a full shot of Clarity twice in your corn field?  No way!  While Xtend may be new to your farm, it was actually supposed to get released 5 years ago.  In other words, many of the issues have gotten worked out over the last 5 years.  Yields are great.  The chemistry is a dramatic improvement over old Clarity and Banvel, and there are dozens of seed varieties available.  We have been planting Xtend for a couple years now, and we’re really excited about both the yield potential and the weed control options we now have going forward.

This article is titled, “How to Use Dicamba Correctly in Xtend”.  In a nutshell, here are the top 5 things I would stress.

  1. Don’t use ammonium sulfate with any form of dicamba.  No AMS means less volatility.
  2. Use drift reduction nozzles.  Both Monsanto and BASF have approved nozzles listed on their websites at xtendimaxapplicationrequirements.com and engeniatankmix.com, respectively.
  3. Use approved spray adjuvants.  If you need a drift control agent or a water conditioner, there are products that are acceptable.  This information is also on the websites listed above.
  4. Most tankmix partners will likely be approved by the time you need to spray them, but check the websites for tankmix options.  By using only products that are approved, you will reduce your risk for drift and volatility.
  5. Make sure the weather is warm.  If your daytime high isn’t going to hit 70 degrees, wait until the weather warms up to get better control from your dicamba product.

Please note that I didn’t even mention to spray when the wind is relatively calm and to always follow label directions.  This would be true for every product you spray in every situation, and it should go without saying.