Dollar spot and ferrous sulfate

The article "Optimizing liquid-applied iron sulfate rate and application interval for dollar spot suppression on golf course fairways" by Soldat et al. presents the results of studies conducted in Wisconsin, Virginia, and Minnesota.

Applications of ferrous sulfate every seven days were more effective than were applications every fourteen days.

Applications of ferrous sulfate at higher rates also showed more dollar spot suppression than at the lowest rates, but higher ferrous sulfate rates also increased the risk of phytotoxicity. The rates…