Answer: Unfortunately, based on your description, I am unable to diagnose the problem for you. There are many different causes for spots on the lawn, such as those described at the following diagnostic web page
As you can tell, it is not always easy to distinguish the causes. I would suggest you work with your local Rutgers county extension to identify the specific cause for the spots and work from there. If a chemical control is needed, they will have the most up to date information on what to use and how/when to use it for best results. I'm sorry I can't be more specific long distance.
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