Q: I am finding brown streaks across my St. Augustine grass and I am seeing the same problem in some of my neighbor’s yards too. What could be causing this problem?
A: Since we talked on the phone and you had several neighbors willing to meet, I went to your subdivision and conducted an extension program called “Troubleshooting Landscapes.” Once I saw your lawns it appeared to be chinch bug damage. Upon further examination we discovered chinch bugs and I was able to show each of you what the insects looked like and how to control them. We discussed proper cultural methods of watering, mowing and fertilization in addition to appropriate chemical applications.
Most people are surprised at the small size of chinch bugs especially when compared to the damage they inflict. At this point, all types of St. Augustine are susceptible to chinch bug damage so scouting for these insects during the summer months is important. Try to alternate the chemical you use and restrict the number of applications of the insecticide according to the label.
Any homeowner can check their own lawns by taking an empty coffee can and removing the top and the bottom to form a hollow cylinder. Sink the empty coffee can into the grass about 2 inches deep in a section between the dead and dying grass. Slowly poor water into the cylinder keeping the water just above grass level and if chinch bugs are present they should float to the top. The adult chinch bugs are black and white; the nymphs are red and white.
Currently, chemicals must be applied to control chinch bugs. There are no cultural practices that will prevent chinch bug damage. Chinch bugs like environments that are hot and dry, so they often start in grass areas where irrigation systems are not overlapping. Check your lawn sprinklers to see that all areas of your lawn are being watered thoroughly, but not over-watered. Remember to water your grass once every 5-7 days in the summer, ¾ inch at a time.