Aaron Hathaway, Kevin Frank and others have been evaluating different products and different application timings for seedhead suppression for about 20 years at the Michigan State University Hancock Turfgrass Research Center. The duo says in MSU Extension newsletter that Embark is no longer being produced, so those who haven’t stockpiled it over the years can no longer use what has always been considered to be the most effective product for seedhead suppression.
Over the years, we have developed growing degree-day (GDD) models to better time applications of Embark, and Proxy plus Primo Maxx. After years of research and talking with other researchers and golf course superintendents, many applications still fail to effectively suppress seedhead production in annual bluegrass greens and fairways. Efforts to suppress seedheads in East Lansing, Michigan, failed in 2018 and many golf course superintendents also appeared to have struggled with seedhead control.