Powdery Mildew is a common problem on bluegrass lawns in shady areas. The mildew fungus, Erysiphe graminis, attacks the surface of the grass leaves, developing a fine, fungal growth that resembles a white powdery substance on the leaves. In dense shade, Powdery Mildew causes the affected areas of leaves to turn yellow, eventually resulting in the yellowing and dying of lower leaves or even in the death of plants. Powdery Mildew develops in areas of dense shrubbery or trees where there is poor air circulation, considerable shade, and high humidity.
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