It is sold commercially as Domain, Fungo, and 3336. Homeowner packaging of thiophanate-methyl is available from Green Light as Systemic Disease Control. Hot and dry weather put additional stress on lawns, making them more susceptible to the various disease pathogens responsible for the summer patch disease complex. While fungicides can be used to help treat these diseases, often the most important treatment is to examine the cultural practices used on the lawn and modify those to promote a healthier lawn. The three primary cultural practices of mowing, watering and fertilizing can seriously stress a lawn if done improperly.
Thatch buildup is often a precursor to more serious problems later in the life of the lawn.
Finally, use core aeration in the fall to reduce thatch buildup. Be sure there are at least 2 weeks of active growing weather left after aerification. Treatment can be repeated in early spring and again the following fall. Cores should be broken up over the turf to mix soil and microbes into the thatch layer. Vertical mowing or power-raking can also be useful but may not be as effective in treating a severe thatch problem.