It reminds me of elves who are also master on nature.
The bridges are made of roots. It take many years to complete. Without any doupt they are very strong and durable. The first one is said to be abble to keep 35 people.
Here an old man who teach the boy how to build a living tree. It is interesting tradition pass by generation to generation.
It isn't a fantasy to live like an elf in this world.