I wouldn't consider hemp as wood. It's a plant, the same plant that produces Marihuana, but yep, on the other hand it's the stem part, it's hard, and it looks like wood. So I don't know.
I have bought (and used) two packages of hemp and I didn't have any problems with them. I can't freeze them because they don't fit on my freezer, so I hope that what cypher says is true
