Dead Lawn--Fix Ph under evergreen trees. Answered
Coniferous trees (pines, etc) acidify soil under em. Lawn doesn't cope wit this too well.
Dump your old boxes of baking soda from freezer/fridge under pine tree. It works. Grass grows better.
I'd do an -ible, but didn't bother to take pics. If you try it, maybe take before + after pics and post an -ible.