Dollar spot loves, dew, fog, and temperature 65-85 degrees and we have had those conditions lately.
As you think about your fungicide program, don’t forget about rotating among different mode-of-action groups. The Chemical Control of Turfgrass Diseases publication from Kentucky does a great job outlining those principles. Don’t forget to look at the active ingredient names and FRAC codes along with the trade name. You might think you are rotating, but you are not. You can read the general info on that page, and/or scroll to the info specific for dollar spot a few pages in.
The Kentucky publication highlights some points about fungicide resistance. In a recent survey of isolates collected in Kansas, nearly all were fully resistant to thiophanate-methyl. That is, the fungus blew through it like it was not even there.
