The last few weeks of hot humid weather has placed pressure on disease control programs through the Midwestern and Eastern United States.  This is especially true for fairway fungicide programs where many superintendents try to stretch as much out of a spray as possible.  Lately, fungicides that might have given 14 day control earlier in the season are break sooner giving only 9 to 10 day control.  The longer lasting systemics are trending the same way. 

In situations where disease symptoms are present and the pathogen is active like brown Patch (the outer “smoke ring” ring is visible) the pathogen needs to be knocked down quickly and then treated to provide extended plant protection.  Should conditions continue to remain favorable for brown patch once disease symptoms appear,  one strategy is to apply chlorothalonil (ex. Daconil Action®, Daconil Ultrex®) followed closely (within a few days) with an application of penthiopyrad (Velista®).