Lawns were under severe stress during last summer's drought, so watch your grass closely this season for potential problems. Though simple tests can identify a white grub or chinch bug infestation, fungal diseases are more difficult to diagnose. An example is Take-all Root Rot, a relatively new disease which can attack both St. Augustinegrass and Bermudagrass.
Take-all patch is characterized by large areas of dead turf in either circular or irregular patterns. These dead areas can range in size from one foot to several yards in diameter. These may first occur on slopes or other areas which didn't get as much water and therefore suffered more stress during the drought. This disease can easily be mistaken for Brown patch or grub damage, but a distinguishing characteristic is extensive root rotting.
Stolons will have lesions or show a brownish discoloration. The fungus is most active during early spring and fall when there is plenty of moisture and nighttime temperatures drop below 70 degrees. Though the best time to chemically treat this disease in the fall, there are measures which can be taken now. Thatch, for example, provides an environment which encourages fungal growth and should be removed. Aerating the soil may also be of benefit.
This disease is difficult to diagnose and control. It also has the potential to live up to its name and "take all" of a lawn. If you suspect a fungal problem, call the Smith County Extension Office for information on sending a sample to the Texas A&M Plant Disease Diagnosis Lab. The cost is only $15.00, and it may save your lawn!
Geneva Thomas, Smith County Master Gardener
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