Is my silver birch tree dead and un-revivable

[Panda]

The pic on the left is another silver birch, the middle is a thorn bush and the bare tree on the right is the one I think is dead, I'm pretty sure I know the answer but I thought it wouldn't hurt to ask before I dig it up incase it can be nursed back to health

 

[MoreRootsMoreFruits]

couldn't really say sorry. is it a bit constrained in that corner? are the roots getting enough air? compared with the other one it looks a bit like there's more grass round the base?