Nice find, but it's freshly cut wood.
As far as I know, you can't use freshly cut woods in a tank.
Pretty sure it leaches toxins into the water that will poison your fish.
If it was possible to put rooted stumps into tanks, it would have been done already. That's why those fish furniture companies create wood like resin decorations, but they look fake to me.
Feel free to correct me if I'm wrong.