Take a look at the trunk cross-section of trees that grew 350 million years ago.
.... would make very interesting pens if you could ever get any !!
https://www.livescience.com/60746-e...ter&utm_medium=email&utm_campaign=20171024-ls
.... would make very interesting pens if you could ever get any !!
https://www.livescience.com/60746-e...ter&utm_medium=email&utm_campaign=20171024-ls