Chinch Bugs
The #1 insect pest of St. Augustine grass. Chinch bugs pierce grass blades and suck out plant juices, injecting a toxin that causes yellowing and death. Damage appears as expanding yellow or brown patches in hot, sunny areas of the lawn during summer.
Chinch bugs (Blissus insularis) are tiny, adults are only 1/5 inch long, but infestations can be enormous. A heavily infested lawn may have tens of thousands per square foot in hot spots.
Identification: Part the grass at the edge of a yellowing patch and look for small black bugs with white wings folded over their back. Young nymphs are bright red with a white band across the abdomen.
Damage pattern: Begins in hot, sunny, drought-stressed areas. Expands outward as the infestation spreads. Does NOT recover after watering (unlike drought stress).
Control: Bifenthrin, permethrin, or lambda-cyhalothrin applied to the affected area and surrounding turf. Repeat in 2-3 weeks if infestation is heavy.
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