Piscataqua Landscaping and Tree Service - Meet the Jack O'Lantern Mushroom! (Also known as Omphalotus olearius.) This fungus grows around oak trees, but generally indicates that the tree is in poor health.
Jack-o'-lantern Mushroom | Sudbury Valley Trustees
Western Jack-O'-Lantern (Omphalotus olivascens) · iNaturalist
Omphalotus illudens, also called jack-o'-lantern mushroom | RECOIL OFFGRID
Omphalotus olearius (The Jack O'Lantern Mushroom)
Jack-o'-Lantern | Missouri Department of Conservation