The most common problem with zoysia has been the insect, chinch bug. Chinch bugs damage the turf by sucking the juices from the plant leaving a yellow to brown area in the lawn. Chinch bugs are hard to spot as they are very small and very close inspection on hands and knees is required. A properly timed application of an insecticide is required to control chinch bugs. Diagnosing lawn problems is a difficult task.
Many symptoms look the same and hot dry conditions make identification even harder.
The best defense against these problems is good cultural practices.