It’s not a cinch, but controlling chinch bugs in St. Augustine grass is possible with careful observation and deliberate steps.
Expanding, irregular patches of dead or stunted grass surrounded by a halo of yellowing, dying grass often provide the first clue to the presence of chinch bugs. These islands of dying grass tend to increase in size and merge as insect numbers increase. Damage can develop rapidly, especially in sunny locations during hot, dry weather.
Chinch bug damage can be confused with certain lawn diseases. For instance brown patch is a common disease affecting the leaf blades of St. Augustinegrass. Brown patch symptoms, however, usually occur in a circular or semi-circular pattern, whereas chinch bug feeding results in irregular-shaped areas of dead and dying grass. Chinch bug damage also can be difficult to distinguish from damage caused by drought.
Reduce your exposure to chinch bugs with these best practices:
- Keep thatch to a minimum with proper mowing. If necessary, employ the use of a vertical mower or aeration techniques if excessive thatch becomes a problem.
- Don’t feed the bugs! Over fertilization not only creates a delectable dining table for chinch bugs, but it contributes to thatch formation.
- Water correctly. Chinch bugs prefer hot, dry environments. Too little watering produces this. On the other hand, over-watering creates an environment that cannot sustain the microbes needed to decompose thatch.
- Guard against stress caused by drought. Drought-stressed lawns are more susceptible to chinch bug infections.
- Choose a chinch bug resistant type of grass.
- Use chemical controls judiciously. Before resorting to chemical controls, be certain chinch bugs are the culprit. Inspect your lawn weekly looking for off-color areas, especially in direct sun, and along sidewalks and driveways. When chinch bugs are present in high enough numbers to cause grass to yellow, they can often be found by parting the grass at the edge of affected areas and examining the soil and base of the turf. Products containing diazinon, chlorpyrifos (Dursban®), or acephate (Orthene®) are suggested for homeowner applications. Where any of these products fail to provide control, apply a synthetic pyrethroid such as permethrin.









