There is a new premix for corn being marketed in Tennessee.  It is called Acuron. I have had several calls about it recently and have found that, like almost all the corn premixes, there is some confusion about what is in it. That confusion is nothing new. A famous extension weed scientist, Marshal McGlamery, coined the term “can ‘em and confuse ‘em” to describe the corn premix phenomena decades ago.  The reason there have been so many premixes marketed in corn was due to the simple fact that all herbicides work better with atrazine. Acuron also contains atrazine along with Callisto, Dual Magnum and a new herbicide, bicylopyrone. Below are some more thoughts on this and other corn premixes:

Acuron (Dual II Magnum + Callisto + atrazine + bicyclopyrone) Rate: 2.5 qts/A

Positives

1. Very good resistance management product with three modes of action for control of many broadleaf weeds.
2. Best way to use this product is to apply it at 1.25 to 1.5 qts/A PRE emergence and then follow with a planned POST application of Halex GT, Capreno or Realm Q
3. This premix can provide excellent control of glyphosate-resistant horseweed.
4. The 2.5 qt/A rate will provide better residual control of Palmer amaranth or annual grasses than comparable rates of Lexar or Bicep II Magnum

Management Considerations

1. 2.5 qts/A rate of Acuron provides 0.62 lbs ai of atrazine.
2. Can be applied POST emergence to corn – Max corn height is 12” tall 

Bicep (Dual II Magnum + Atrazine) Rate: 1.6 to 2.6 qts/A

Positives

1. Has been used on more corn acres than any other corn premix.
2. Provides good all around weed control with good crop safety.

Management Considerations

1. 2 qts/A rate provides 1.55 lbs ai of atrazine.
2. The herbicide Expert is essentially Bicep premixed with glyphosate.

Harness Xtra 5.6, Degree Xtra, Breakfree ATZ (Acetochlor + Atrazine) Rate: 1.7 to 3 qts/A for Harness Xtra or 2.9-3.7 qts/A for Degree Xtra or 2.2 to 3 qts/A for Breakfree ATZ.

Positives

1. The non-encapsulated acetochlor formulations Harness and Breakfree have provided pigweed and grass control comparable to Dual II Magnum.
2. Degree Xtra is an encapsulated formulation that releases slowly over time.  Limited research has shown about a week longer residual control of pigweeds compared with other acetochlor formulations. 

Corvus (Balance + thiencarbazone) Rate: 5.6 ozs/A

Positives

1. Low use rate can be very convenient.
2. In our research it has provided good pre emergence control of most broadleaf and grass weeds.
3. It will provide good glyphosate-resistant horseweed and Palmer control.

Management Considerations

1. Can be applied up to V2 corn.
2. Corvus works best applied PRE and then followed with a POST applied application of Halex GT or Capreno.

Regardless of whether the corn being managed is Roundup Ready or not, the best overall weed control will most often be achieved with some kind of two pass program.  One reason this works best is due to being able to apply more atrazine in two passes (2.5 lbs/A) compared to all in one application (2 lbs/A).