Reddit user Independent-Design17 proposed a fascinating connection between Elden Ring's Erdtree and the Australian Christmas tree, Nuytsia floribunda. Superficial similarities exist, particularly when comparing the game's smaller Erdtrees to the Nuytsia. However, the parallels run deeper.
Elden Ring lore depicts the Erdtree as a guide for the souls of the deceased, explaining the catacombs at its base. Similarly, Aboriginal Australian culture views Nuytsia as a "spirit tree," with each flowering branch representing a departed soul, its vibrant color echoing the sunset, the believed destination of spirits.
Further strengthening the connection is Nuytsia's semi-parasitic nature; it draws nutrients from neighboring plants. This mirrors a popular fan theory about the Erdtree's parasitic nature, suggesting it usurped the life force of an ancient Great Tree. However, game lore clarifies that references to a "Great Tree" are mistranslations, actually referring to the Erdtree's own extensive root system.
Whether FromSoftware intentionally drew inspiration from Nuytsia floribunda remains a mystery, known only to the developers.