Wet stain on unfinished floor

Q: We are in the middle of installing hickory hardwood floors. I’ve been covering up what he has laid with towels and sheets to somewhat protect it, but we have found a stain of some sort upon picking up the towels. I suspect it is either dog urine, or a spot where a big wet dog laid down and some of it went through the towel onto the unfinished floor.

I’m afraid to do anything for fear of making it worse. Will sanding it take it out? Is there a product and technique I can use to remove it? Thank You.

A: Yes, sanding should be able to remove this. It is very likely just a surface stain.