I have trees lining the perimeter of my back yard. Its 60ft wide. I live on an island and the soil isnt great so i dug up the roots laid lime and topsoil the the sod. Both times. I watered it every day. Both times it lasted 3 or 4 weeks then slowly died. Ive tried seeding aswell. It will produce some very weak thin grass then it will die aswell. Seems like the only thing that will survive out there is weeds. Could it be possible that the tree roots running through the yard are starving the grass of water?