Applying Herbicides


Used properly, chemical suppression is an excellent way to enhance grassland habitat for bobwhite quail and other wildlife. Without disturbance, both warm-season and cool-season grass fields often become dominated by dense sod or a single species of grass (monotype). This reduces habitat quality for a number of wildlife species.

Herbicides can improve plant diversity by reducing the vigor and abundance of plants that crowd out other plants. Sprayed areas will soon produce a wide array of grasses, forbs, legumes, seeds, and insects.

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Use herbicides carefully

Remember, for habitat-management purposes, spraying is not meant to completely eradicate vegetation but to reduce the vigor and abundance of unwanted plants.

  • Use herbicides at label rates to set back, or suppress, but not eliminate vegetation.
  • For best results, apply herbicides when dominant vegetation is actively growing. Weather conditions influence vegetation growth and may narrow these dates.
  • Use grass-specific herbicides on fields rich with native wildflowers.

Always read and follow herbicide label directions. 


Recommended Spray Dates

(Conservation Reserve Program spraying dates may differ)

Cool-season grasses (fescue, brome, orchard grass, etc.) — March 15 to May 15 or October 1 to December 1

Warm-season grasses (Indian grass, big bluestem, etc.) — May 1 to September 1

For best results:

  • Spray different areas of the field in different years.
  • Apply spray in blocks or strips on one-third (preferred) to one-half of the field each year.
  • Make strips 25–75 feet wide and as long as possible.
  • Separate strips from each other with an area of undisturbed vegetation twice as wide as the sprayed strip.
  • Have strips follow the contour of the field to prevent erosion.
  • After one year, spray a new block or strip of similar size next to the unsprayed area.
  • Spray the final undisturbed block or strip the third year. This develops adjoining strips of vegetation of three different ages, providing three different stages of plant succession.
  • Re-treat sprayed areas as needed to maintain desired plant diversity.

In areas of heavy growth

Prescribed burns or mowing may be needed to remove dead or tall, thick vegetation before spraying. Allow the burned or mowed vegetation to grow 6–8 inches before spraying. You can also disk or burn after the herbicide application to further enhance habitat conditions.