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FAQs about chemical use in forest management

  • The primary reason that spraying occurs is to clear plants and seedlings so workers can plant new seedlings, or so that seeds spread by desirable seed trees in the area can thrive without competition. In other situations, herbicide is used to help mitigate the impact of invasive plants, pests and diseases to help sustain the ecological, economic and social benefits of Michigan forests for current and future generations.
  • Each decision to apply herbicides goes through a multistep evaluation process to make sure the right treatment is being used in the right place at the right time. Considerations include the goal of the spraying, the terrain, whether nonchemical alternatives are available and what the most effective minimum dose of herbicide is for the situation.
  • Roads into an area to be sprayed are marked with signs that include information about the herbicide used and related safety precautions, such as not entering the site for two days after the date of spraying.
  • Avoid eating foraged foods from the sprayed site for the remainder of the season. Food plants that have been sprayed will die within about two weeks.
  • Please follow the guidelines for humans using the area. If the posted signs state that people should remain out of the area for two days, pets should also be kept out of the area. Guidelines for livestock may differ and should follow product labeling.
  • No. Exact dates and times of herbicide application depend on the weather. If it is rainy or windy, herbicide will not be applied.
  • Herbicide is sometimes applied using a small helicopter or drone. Other times, herbicide is applied from a vehicle on the ground. Forest Resources Division staff will choose the safest and most effective way to deliver herbicide to the area being treated. It is always done at the direction of a licensed herbicide applicator.

    Strict labeling governs the application and use of each individual pesticide. FRD staff and contractors always follow the label.

    A day or two before spraying, signs will be posted that say which herbicide is being applied. There also will be information as to when you can safely enter the treated area. Please do not enter the treated area for two days after applications. The signs will remain up at least 30 days after application or until the vegetation is noticeably dead.

  • You will see spots developing on the foliage of the hardwood trees the first few days. Then the foliage will start to turn yellow and ground vegetation will turn brown. Within 10 days, you will see both the hardwood foliage and the ground vegetation brown and dying. The vegetation on the site will rot over the course of the summer.