Found growing on the side of a birch tree in a forested park. None of the features in the visual key in lab really apply to this fungi. Fungi is Shelf/ Polypore. Fungi are about 5-6in thick. Upper surface has perennial lines. Bottom Surface is white. Not gilled. Has pores. Based on the supplementary material it looks most similar to Fomes fomentarius “Hoof Fungus”

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