Answer: Unfortunately, based on your description I am not able to diagnose the yellowing. Yellowing can be caused by many different factors ranging from chemical spill to overfertilizing to disease to insects to mowing too short and scalping the lawn. I would suggest you consult both with your lawn service, and also with your local Rutgers county extension to obtain a diagnosis of what is causing the spots. Knowing that, you can decide how to proceed. If a chemical control is needed, the county extension will have the most up to date information on what to use and how/when is best to apply for maximum results.
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