Never heard or read that before about tree pollinating itself developing empty husk. A 100 year old Chinese chestnut is believable but original Asian trees are more bush like. Blight introduced early 1900. Trees dying quickly so they get trees from Asia and Europe. Bring more blight into the country. If you want to get a second opinion on that tree you can contact the American Chestnut Foundation. You can send samples to them and they will tell you what kind of chestnut that is. Good luck with your trees.