Components and Ratios of Pre-mix Herbicides for Use in Corn and Grain Sorghum

Many herbicide options for field corn and grain sorghum comprise multiple herbicide active ingredients to broaden the spectrum of weed species the product will control. Herbicides are also combined to include additional herbicide modes of action so that development of herbicide-resistant weeds can be prevented or delayed. Knowing the amount of the individual herbicides in the pre-mix is useful for deciding if additional product should be applied to further improve weed control.

 

The following table lists several pre-mix herbicides that are labeled for use in field corn and grain sorghum and the equivalent rates of the individual herbicide components. Use rates for pre-mix herbicides are based on label recommendations for medium texture soils with 1.5% organic matter and pH of 6.5. Use rates can vary depending on crop, soil characteristics, and planned follow-up herbicide applications. Before using any herbicide, always consult the label for appropriate rates, application timing, tank-mix partners, plant-back intervals, geographic restrictions, and other special instructions.

 

Table 1. Pre-mix Herbicides for use in field corn and grain sorghum and the equivalent rates of individual herbicide components.

 

^a Check product label for appropriate application timing.
^R Restricted use pesticide.

 

Abbreviations:

• oz = ounce 
• fl oz = fluid ounce 
• gal = gallon 
• pt = pint 
• qt = quart 
• lb = pound
• ai = active ingredient
• ae = acid equivalent
• DF = dry flowable
• L = liquid
• SG = soluble granule

 

Additional Resources

For more information on herbicide modes of action, please see OSU Extension Fact Sheet PSS-2778 “Understanding Herbicide Mode of Action.”