Rhizoctonia Blight, often referred to as Brown Patch (see photos below), is active each year in our area and is common, most particularly on our fescue turf. Brown Patch thrives in conditions of continuously wet foliage, high humidity, and high temperatures. Brown Patch causes roughly circular areas of discolored turf. The patches may range in size from a few inches to several feet. Extended infection periods can result in the death of some turf, however it is more common for the fungus to kill only the foliage and not the crown area of the plants. Often times the damage is only superficial and the turf will recover in two to three weeks once weather conditions break the fungus’ cycle.
We must plan ahead and develop good maintenance practices early in spring in order to overcome these stress problems that surface in summer. Certain cultural practices will help reduce Brown Patch as well as other turf diseases. Disease incidence and severity is definitely minimized through good habits. Raising mowing heights and increasing mowing frequency without bagging is always the first suggestion we make to those experiencing disease problems on turf. Other maintenance practices that will improve turf quality include reducing compaction through core aeration, proper irrigation, using quality slow-release fertilizers, and introducing certain cultivars of grass.
Fungicides may be applied to suppress disease development in certain instances. Newer products are giving much better results than what was previously available, however applications are costly.