If you think bugs are causing dry spots in your lawn. Think about the symptoms that you are observing. Do the dry spots in your lawn show up in dry weather? Do you have a sprinkler system? Is it a recurring problem with no visible bugs? Sounds like lack of moisture to me.
Sprinkler systems can have many possible reasons for poor or inadequate coverage. A spray head out of adjustment, plugged or broken can cause dry spots. A shrub, tree, or grass growing over the head can cause poor coverage also. There may not be enough sprinkler heads for correct coverage. The pressure may be too low for acceptable coverage. There may be too many heads on each zone. Nozzle size needs to be considered for matched precipitation. You should never install rotors and popups on the same zone.
Place some cans in the lawn over the dry spots and green areas as a good comparison while the sprinklers are running. Let them run until there is enough water in the cans to compare the amounts. This will be a good way to check your coverage.
Check several areas in the dry and green areas of the lawn with a soil probe. You should pull out a 6 to 8 inch core. You will be able to tell the difference if it is a moisture problem. If moisture is equal in both dry and normal lawn cores you may well have a pest problem. Don’t just randomly treat for bugs until you have determined exactly which pest is the culprit. If you need help call a lawn care or pest control business. You can contact philthegardener by leaving a comment here or on the Questions For Phil The Gardener page. I will be glad to help you.