How to treat dead looking grass?
Ok I will presume you are referring to Bluegrass, and by “dead looking” you mean brown instead of green. Generally this just means that the grass isn’t getting enough water. Bluegrass is incredibly resilient and will come out of dormancy with a little help (water). The other possibility could be a root-level bug eating the roots. Typically I have found that grubs will do that: eat the roots below ground, killing the grass blades. There are a whole host of pesticides for that purpose. So: make sure it’s getting enough water, use a bug killer and perhaps high nitrogen fertilizer and it should bounce back.
