hoping to put some outside stuff in the crabitat

[Hermitsandplants]

so i was outside looking for stuff to put in my hermit crab tank, and came across the following I was hoping to use.
-river rocks
-oak leaves
-driftwood
-dead insects
-snakeskin
-random bone(probably mouse or smth)

Are these safe? I don't want to give my hermit crabs something that will make them sick, but hopefully can give them some new stuff to play with.

Thank you

[curlysister]

There will be people who are very nervous about bringing outside bugs and germs into the tank, and some who aren't. If may also depend on where we live, and what kinds of things live in our climates.
I bring in all kinds of leaves from my yard and garden in summer, and dry some for the winter. I don't use any insecticides or pesticides in my yard. I do live in a rural area where farming chemicals are sprayed, so I am careful to avoid picking soon after any spraying, and I pick new growth rather than leaves that have been there for a while.
I have driftwood from inland lakes in my tank. I scrubbed it in some salt water (kitchen salt is fine, doesn't have to be Instant Ocean) and let it dry in the sun before putting it in the tank.
I would be a bit more careful with things like dead bugs - you don't know what killed them, like if it was an insecticide or pesticide. And not knowing where the bones are from or how long they have been there, I might be careful with those too. I don't know anything about snakes, so can't really help you there LOL.
I have collected moose poop from my yard - I only collect in spring because I know that the branches and leaves they have been eating all winter won't have been sprayed with any chemicals like in summer.