Driftwood
Hello Blue...
Any natural wood will work in your tank. It's better than the commercial kind, because the natural stuff won't leak the tannins into the tank and turn the water that tan color.
The more dense wood will need to be weighted down with rocks or you can attach plants to it and let it float. My tanks are full of the local pieces from river and pond areas.
Make sure you observe any laws prohibiting this type of activity.
B