Hoof Fungus (Fomes fomentarius)

Hoof Fungus (Fomes fomentarius)

Observation - Hoof Fungus (Fomes fomentarius). Description: On Silver Birch, and I am thinking Hoof Fungus, Fomes fomentarius, but the underside is saying I am wrong..?

On Silver Birch, and I am thinking Hoof Fungus, Fomes fomentarius, but the underside is saying I am wrong..?