After the fall when they installed tall fescue sod on a slope in their yard, Mary reported that she and her husband had a beautiful lawn.  She mowed twice per week with a good mower.  Prior to planting, Mary had even taken the soil to the County Extension Office, and fertilized only according to their directions, through May.
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But in July 2004, after 20 continuous days of rain, high temperature, and high humidity, the lawn started to brown.  There were no signs of grubs.  Mary treated twice with fungicide within a week, and started bagging the clippings.