Use the sapwood directly under the bark on any whitewood such as maple, ash, oak, hickory, hhb, etc. Work it down to 2" wide by 2" thick and keep it stored in your house for a couple months. After that, work your limbs down to 3/4" thick and let it sit another couple weeks. It should be ready after that. Keep an eye on it as its drying to make sure it doesnt warp.