Below photo courtesy @Lottery_Ticket
The area has a very interesting and unusual look as seen from the road. It seems to be a combination of the tree's scale relative to its neighbours and the vividly green vegetation that surrounds it.
I remember thinking the tree looked fake when I first watched Ab Aeterno. I guess this is another example (the London scene with Widmore and Sun also comes to mind) where reality seems unreal.
I didn't fully catch it on first viewing, but I believe these two shots are meant to capture the same location separated by 140 years. Presumably the little 1860's sapling grows into the majestic 21st century tree.