Birch Tree

Most if the  birch trees are quite golden now but the oak are still green.The oak are the last to get their leaves in our garden  ( We do not have any ash trees which are normally last)  and the last to lose them. We have birch leaves falling like snowflakes just now.
I hear we are to have 5 tiers, I am not sure if this will be a good idea. Time will tell!