You could dig & fill those spots, but I'm not sure it's worth it. The Tif should be back in a few weeks & it sounds like you have other repairs to deal with. If you decide to fill, just use a clean sharp sand to prevent settling.

You can blame the roofers for the nails. Find a rental company that has a magnet on wheels. Or call them back to address the nail problem. We just had a new roof put on our building and there were nails in the parking lot after they swept, so they can be hard to get in the best circumstances.

However, you cannot blame the roofers for the fungal disease that caused your large circles. Gasoline does not spread out 10 feet and does not always kill grass anyway. Diesel, on the other hand, coats the plants in oil which kills them quickly. No, for this problem you will have to blame Mother Nature and the rainstorms that brought you daily amounts of an inch or more for 4 or more days (a month ago). Your lawn has a fungal disease. When the disease takes the shape of a circle it's called fairy ring. Quite often there is no visible effect in the grass, but in your case, clearly it's killing the grass.

The organic approach is to apply ordinary corn meal at a rate of 20 pounds per 1,000 square feet to the entire yard. I can't help you with the chemical solution, because corn meal has always worked for me. Others will be by soon and can help you pick a chemical product if you want one.

Dchall, no these are spots related to gas burns. They're all 8-10 inches...not feet. They had begun to gray out the evening of the day they left and then two days later completely straw colored or just plain dead. I was just wondering how to treat these or simply leave them alone and wait for them to grow back on their own.

It's completely possible I'm just misinformed though. I've never heard of a fungus that completely annihilates such a targeted, small area with 24-48 hours from first onset though.