wow thats just splinters, i would not use that kind of matrial in my terrarium, i would worry that my snake's could die if they eat it.
i use only cocopeat (i think it's called) in my terrariums, it is a brown substans made from coconuts, just like this
Bucotec
i never had any problems with it, in denmark you can buy it in most petstores, and i think it's the same in usa.
they are like bricks, and then you just add water, and you will get the best terrariumsoile ever
sorry for my bad english, hope you understand