Question
I live in Cleveland Ohio and during this summer I have lost almost all of my grass under my big oak trees. This has never happened in previous years. We had a period of drought although not bad. When should I try to reseed and what type of grass grows best in shady areas.

Also my burning bush - which is almost 6' high and 3' in dia. has lost most of its leaves - any ideas?  

Answer
Under an Oak Tree is a TERRIBLE place to Grow Grass.

But you asked, so I'll answer.

Red Fescue Grass boasts the best shade tolerance of all Cool Season Grasses.

That said, consider thinning out your Trees and opening up the Tree canopy to help get more light down to the ground.  Water as needed.

Sorry, I cannot help you with the Burning Bush; I have not grown this yet.