Repurposing repurposed wood beams

I'm renovating a cabin that was built in 1950. Everything was repurposed to build then. I saved the roof rafters in hopes to use them somewhere and I think I landed on door trim. I took them out in July and they sat outside until today when I brushed the snow off then and brought them inside. I'm still debating on if I want to take a hand planer to them to take off the old finish and splinters. If I do I'd have to stain and seal, if not I'd like to just use a hard sealant.

Few questions:
1. Should I be treating these somehow/way?
2. They were dry for maybe a hundred years, they have been in the elements for 6 months now. Roughly 2.5"x5". How long to dry?
3. Can anyone name the species of wood? I did plane one down a little.

Thank you