I'm working this osage stave. Got it down to one ring and started removing belly wood when this spot appears on the belly. It's 2 1/2" long and 1/2" wide. It feels just as solid as the heartwood around it. It isn't visible on the back and as you can see from the pic I still have a ways to go on the belly.. Maybe it will disappear as I work the belly down. Just curious as to what may have caused this. The stave does have reddish streaks on the back. It's from SE Ohio if that makes a difference. Any ideas? Thanks, Steve