Tankmixing Chemicals

Are The Chemicals Compatible?

By Amanda Huber
 

 

Tankmix applications have possible advantages and disadvantages.
It may be possible to:

• Increase the spectrum of pest control
• Decrease time and cost of labor
• Lessen vine damage
• Lessen damage to the soil due to compaction.

Avoid these possible disadvantages:
• Reduced control
• Increased crop injury due to phytotoxicity
• Physical incompatibility of chemicals to be applied
• Different spray volumes or adjuvant recommendations for components.

Be aware of legal issues when tankmixing agrichemicals:
• The label is the law. If the mix is not permitted, do not use it.
• Always follow the more restrictive label. Remember that manufacturers will not guarantee product performance if the chemical is used in a way other than described on the label.

To overcome incompatibility:
• Increase the rate of application for a chemical
• Use or change an adjuvant
• Change a spray volume.

When tankmixing chemicals, add products in the following order unless otherwise directed on the product label:
1. Small amount of water, and begin agitation
2. Water-soluble packets
3. Wettable powders as a slurry
4. Dry flowables or water-dispersible granules
5. Liquid flowables
6. Emulsifiable concentrates (oil concentrates)
7. Remaining water
 

Managing pests is critical in optimizing peanut yield and quality. Applying combinations of agrichemicals is an efficient practice with known benefits. Producers may reduce the cost of pest management by limiting trips across the field. Fewer passes across a field is not only more convenient, it also reduces vine damage and has the potential to increase control of particular pests and broaden the spectrum of pests controlled.

But tankmixing of agrichemicals has difficulties and disadvantages. Chemicals may be physically and/or biologically incompatible. Adjuvant and spray volume recommendations may differ. Certain combinations may actually reduce pest control or increase plant damage due to phytotoxicity.

To choose an effective tank mixture, begin with the product label. The label is the law. Product labels provide federal regulations concerning tank mixing; always follow the more restrictive label.

While farmers may legally tankmix any chemicals as long as no product label restricts tankmixing, certain tank mixtures can cause the peanut crop to suffer. Product labels do warn about some potential problems, but they do not clearly address other issues. And manufacturers do not guarantee product performance when their chemicals are used in ways other than described on the label.

Peanut producers are most likely to apply combinations of herbicides, fungicides, insecticides, plant growth regulators and/or foliar fertilizers. To make these combinations work, a producer needs to be able to predict unfavorable interactions. The tables that follow on pages 14 and 15 outline some of the problems that have occurred with tankmixes applied in research trials conducted by universities in the peanut belt of the United States.

Editor’s Note: The information presented here is only part of the information bulletin: Tankmixing Chemicals Applied To Peanut Crops: Are The Chemicals Compatible from the North Carolina State University Cooperative Extension Service. To view the entire bulletin, go to their Web site at www.peanut.ncsu.edu/ag653_web.pdf.

 
 
Compatibility Of Postemergence Herbicides With Fungicides Applied To Peanut*
Herbicide Weed Species Fungicides That Did Reduce Weed Control Fungicides That Did Not Reduce Weed Control
Arrow with crop
oil concentrate
Broadleaf signalgrass Bravo Weather Stik, Headline Folicur
Large crabgrass Bravo Weather Stik, Headline Folicur
Texas Panicum Bravo Weather Stik Folicur, Headline
Basagran with
nonionic surfactant
(80/20 blend)
Yellow nutsedge Bravo Weather Stik plus Tilt, Kocide, ManKocide Abound, Folicur, Dithane F-45, Omega 500, Tilt, Stratego
Blazer with
nonionic surfactant
(80/20 blend)
Smooth pigweed Folicur, Kocide Abound, Bravo Ultrex, Bravo Weather Stik, Bravo Weather Stik plus Tilt, ManKocide, Omega 500, Tilt
Butyrac 200
adjuvant**
Entireleaf morningglory   Abound, Bravo Weather Stik, Endura, without Headline, Omega 500, Stratego
Sicklepod Abound, Bravo Ultrex, Folicur, Kocide, ManKocide Bravo Weather Stik, Echo, Headline
Smooth pigweed Abound, Bravo Ultrex, Bravo Weather Stik, Folicur, Kocide, ManKocide, Omega 500, Rovral, Tilt/Bravo Echo, Rovral
Tall morningglory   Abound, Bravo Weather Stik, Folicur,
Headline
Cadre with
nonionic surfactant
(80/20 blend)
Broadleaf signalgrass   Abound, Bravo Weather Stik, Folicur, Headline
Large crabgrass   Abound, Bravo Weather Stik, Folicur, Headline
Texas panicum Folicur Abound, Bravo Weather Stik, Headline,
Moncut, Tilt/Bravo
Sicklepod   Abound, Bravo Weather Stik, Folicur,
Headline, Moncut, Tilt/Bravo
Yellow nutsedge   Abound, Artisan, Bravo Weather Stik, Folicur, Headline, Moncut, Tilt/Bravo, Stratego
Cobra with
nonionic surfactant
(80-20 blend)
Redroot pigweed    Bravo Weather Stik, Headline,
Asana XL, Karate Z
Entireleaf morningglory    Bravo Weather Stik, Headline,
Asana XL, Karate Z
Spurred anoda Headline Bravo Weather Stik,
Asana XL Karate Z
Eclipta    Bravo WeatherStik,
Asana XL, Karate Z
Poast with crop
oil concentrate
Broadleaf signalgrass   Abound, Bravo Weather Stik, Folicur, Headline
Large crabgrass Abound, Artisan, Bravo Weather Stik,
Folicur, Headline
Endura, Omega 500, Stratego
Texas panicum   Abound, Bravo Weather Stik, Folicur,
Headline
Pursuit with
nonionic surfactant
(80/20 blend)
Smooth pigweed Kocide, ManKocide, Omega 500 Abound, Bravo Ultrex, Bravo Weather Stik, Bravo Weather Stik plus Tilt, Dithane F-45, Folicur, Tilt, Tilt plus Montero, Tilt plus Stratego

 

Compatibility Of Postemergence Herbicides With Fungicides Applied To Peanut (continued)*
Herbicide Weed Species Fungicides That Did Reduce Weed Control Fungicides That Did Not Reduce Weed Control
Select with
crop oil concentrate
   
Broadleaf signalgrass   Bravo Ultrex, Bravo Weather Stik, Bravo
Weather Stik plus Tilt, Folicur, Omega 500, Tilt
Goosegrass Bravo Weather Stik, Bravo Ultrex,
Bravo Weather Stik plus
Folicur, Omega 500, Tilt
Large crabgrass Abound, Artisan, Endura, Bravo Weather Stik, Folicur, Headline, Kocide, ManKocide Omega 500, Stratego
Texas panicum Abound, Bravo Weather Stik, Bravo Ultrex, Bravo Weather Stik plus Tilt, Echo, Kocide, ManKocide, Tilt plus Montero Dithane F-45, Folicur, Omega 500, Tilt plus Stratego
Strongarm with
nonionic surfactant
(80/20 blend)
  
Common ragweed Abound, Bravo Weather Stik, Folicur, Headline  
Morningglory   Abound, Bravo WeatherStik, Folicur,
Headline
Florida beggarweed Headline Abound, Bravo WeatherStik, Folicur
* Some products may no longer be in use or may have different trade names, but since they were used in the experiment, they are included in the table.   
Results are from replicated university trials conducted in Georgia, Florida, North Carolina and Texas. Compatibility of Butyrac 200, Poast and Select with fungicides has been evaluated more extensively than compatibility of fungicides with Basagran, Blazer, Cadre and Pursuit. Agrichemicals were applied with small-plot spray equipment with ample agitation (shaking) to keep solutions thoroughly mixed. Product labels that prohibit mixing agrichemicals supersede this table. Physical compatibility of some mixtures may be an issue.

 

Compatibility Of Postemergence Herbicides With Other Herbicides, Foliar Fertilizers And Plant Growth Regulators Applied To Peanuts*
Herbicide** Products That Did Reduce
Weed Control
Products That Did Not Reduce
Weed Control
Arrow with crop
oil concentrate
Cadre, Storm  
Butyrac 200 without
adjuvant ***
  Boron Xtra, Karate Z, Manganese Xtra, Solubor, Techmangum
Poast with crop
oil concentrate
2,4-DB, Basagran, Blazer, Butyrac 200, Dual, Pursuit, Storm Apogee, Karate Z, Outlook, Solubor
Pursuit with
nonionic surfactant
(80/20 blend)
Basagran Boron Xtra, Manganese Xtra, Solubor, Techmangum
Select with crop
oil concentrate
2,4-DB, Basagran, Blazer, Cadre, Pursuit, Storm Apogee, Boron Xtra, Karate Z, Manganese Xtra, Solubor, Techmangum
*Results are from replicated university trials and scientific literature. Compatibility of some combinations has been evaluated more extensively than compatibility of others. Product labels that prohibit mixing agrichemicals supersede this table. **Combinations of broadleaf/sedge herbicides often control a wider spectrum of weeds than either herbicide applied alone. See Peanut Information, AG-331, for effectiveness of such tank mixtures.***Farmers and commercial applicators have observed physical incompatibility (settling in spray tank) when 2,4-DB (several formulations) is mixed with manganese-containing products. In the university trials reported here, the herbicide solution was constantly agitated to prevent settling. 
 
Source: Tankmixing Chemicals Applied To Peanut Crops: Are The Chemicals Compatible from the North Carolina State University Cooperative Extension Service. To view the entire bulletin, go www. peanut.ncsu.edu/ag653_web.pdf. Always read and follow label directions with any chemical product.