Steadfast IS

  • Herbicide


  • 2

Steadfast IS herbicide is your go-to solution for control of grasses and volunteer canola in field corn. It comes in a low use rate extruded WG formulation for easy measuring and mixing. Steadfast IS comes with a built-in crop safener allowing for a wide window of application and use on low heat unit corn hybrids.


Proven control of annual grasses

Steadfast IS provides dependable post-emergence control of key annual grasses such as green foxtail and wild oat. It also provides control of volunteer canola including glyphosate-resistant types

Crop protection under a wide range of conditions

Steadfast IS contains isoxadifen, a crop safener allowing for use on short season field corn hybrids and in regions with low heat units. It also provides for a wide application window up to the 8-leaf stage of corn.


Below lists the crops that Steadfast IS herbicide can be used on.


Corn, Field (Zea mays ssp. mays)

Weeds Controlled

  • Foxtail, Green
  • Canola, Volunteer
  • Oat, Wild
  • Wheat, Volunteer


Now registered for Eastern Canada.

  • Registered
  • Unregistered

Technical Specifications

  • Application Method

    Apply with ground equipment only.

    Do not apply during periods of dead calm. Avoid application of this product when winds are gusty.

    Do not apply with spray droplets smaller than the American Society of Agricultural Engineers (ASAE) medium classification. Boom height must be 60 cm or less above the crop or ground.

  • Rates

    66.5 g/ha (27 grams/acre)

  • Application Rate

    Apply 27 g/ac of Steadfast IS herbicide as a broadcast spray.

    Conventional field corn: Steadfast IS must be tank mixed with a non-ionic surfactant at 2L/1,000L (0.2% v/v).

    Glyphosate-tolerant field corn: Steadfast IS can be tank mixed with glyphosate at 900 US gal/ha. When tank mixed with glyphosate, the addition of a non-ionic surfactant is not required.

  • Application Timing

    Field corn: 

    • Eastern Canada: spike to 8-leaf (V6)
    • Western Canada: spike to 6-leaf (V4)

    Annual grasses: 

    • 1- to 4-leaf (up to early tillering)

    Volunteer canola: 

    • Cotyledon to 5-leaf
    • Steadfast IS must be applied only when the temperature in the 24 hours before and after application ranges between 5°C and 30°C. Temperatures beyond this range increase the potential for crop response.
    • Make only one application per growing season.
  • Packaging

    Case: 6 x 540 g bottles

    Acres treated: 20 ac/bottle

  • Crop Rotation
    • 4 months: winter wheat
    • 10 months: spring wheat (including durum), oats, barley, canola, soybeans, dry beans, white beans, chickpeas, potatoes, sunflowers, corn (sweet or seed), field peas, lentils and flax
    • Anytime: field corn
  • Tank Mixes


    • Glyphosate (glyphosate-tolerant field corn only) 
    • Adjuvants: When using Steadfast IS herbicide in conventional corn, it must be tank mixed with a non-ionic surfactant at 2 L/1000L (0.2% v/v)
  • Additional Information

    The pre-harvest interval for Steadfast IS is 30 days for corn (silage, fodder or grain).




Before use and for complete product information, please read and follow label directions.

East Field Guide
View a comprehensive listing of information on Corteva Agriscience products available in Eastern Canada.