I would say not chaga. The tree doesn't look like birch, the bark I can see from the pic looks like tulip poplar. I do find those growths on tree but they end up being burls. Take an axe and try to cut it off at the tree line, chaga will be like a dense cork with a white grain running thru it. Chage doesn't have a very heavy mushroom smell. Cut it off and see I'm not 100% sure. My main computer crashed I had a ton of chaga pics on it.