Have you noticed any abnormalities in your bermudagrass or zoysia lawn this summer? The symptoms I am referring to are small tufted clumps of light green to yellow grass blades that have shortened internodes and swollen leaf tissue. They resemble “cabbage heads” or “witches brooms”. In bermudagrass and zoysia one side of the terminal leaf may be yellow or white and the leaf is curling back into the apex of the shoot resembling a “buggy whip”.
Tiny microscopic mites that are so tiny they can only be seen with a 20X hand lens or microscope could be the culprit. They live and feed beneath the sheath of each grass blade making it very difficult to control them with chemicals. The good news, if there is any, is that they are only associated with these two turf species and they generally are not a serious problem, except when conditions are very hot and dry and there is insufficient irrigation and low fertility.
Management strategies include collecting leaf clipping when mowing and destroying them to remove feeding mites, then provide irrigation, if possible, and keep the turf healthy and growing vigorously so the turf can outgrow the damage.
Chemical control, even though difficult, is possible. Products containing lambda-cyhalothrin (Scimitar, Battle, Spectracide Triazicide) are registered for mites in turfgrass and repeat applications can keep the mite population suppressed. It is the responsibility of the pesticide applicator to read product labels and use accordingl.
Published July 24, 2006
Dr. Wayne Wells is an Extension Professor and Turfgrass Specialist. His mailing address is Department of Plant and Soil Sciences, Mail Stop 9555, Mississippi State, MS 39762. email@example.com