Answer: Leaf spot is a fungal problem that is usually best managed by cultural controls and using resistant grass varieties -- and hoping for better weather. I would suggest you work with your local county extension to obtain a specific diagnosis of the problem and then, if a chemical control is needed, they will have the most up to date information on what to use and how/when is best to apply it to maximize results. In the meantime, here is some detailed information on leaf spot fungus in the lawn you may find helpful. You may need to cut and paste the complete url into your browser to make it work correctly.
I hope this helps.
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