Ha! Yes, now that you mention weirwood (and I had to go look it up too, lol) it is kind of similar, but much bigger. And I don't doubt your inspiration point being original... I did pretty much the same thing with a whole map one time. People made comments that it looked like Westeros and I had to go look it up that time too to see what they were talking about. I had a very different concept for my setting.