Question

What argument does Muir give for protecting the redwoods

Answer 1

they take a very long time to grow and they are god's trees and he protects them from natural disasters. Also once these trees are gone, they are gone forever.

Answer 2

Muir argues that the redwood is really important in order to sustain the ecosystem around it.
So, by Conserving the redwood and protect everythinga round it., we pretty much make an investment to keep the availability of natural resources around it for a long period of time,