Source: Mark Loux, Ohio State University

Mark Loux, Ohio State University, offers several tips regarding marestail biology, resistance and control as it relates to spring burndown/residual herbicide applications.

  1. The majority of the marestail populations in Ohio are resistant to glyphosate or ALS inhibitors (FirstRate, Classic, Synchrony, Canopy EX, etc) or both types of herbicides. 

  2. Comprehensive burndown programs that are usually effective on marestail include combinations of herbicides.

  3. Options for control of large marestail (10 to 20 inches), include a high rate of Ignite (32 to 36 oz) in combination with metribuzin. 

  4. Marestail is capable of emerging throughout much of the year, and substantial emergence can occur between now and mid June. 

  5. We have had good success with April applications of a combination of burndown and residual herbicides, so we suggest applying anytime from now on that the field is fit for traffic.

  6. What if I applied herbicides last fall? This does not necessarily change the recommendations presented previously in this article.

Original press release