Reddit user Independent-Design17 proposed an intriguing connection between Elden Ring's Erdtree and the Australian Christmas tree, Nuytsia floribunda. Superficial similarities exist, particularly when comparing the in-game depiction of smaller Erdtrees. However, fans have uncovered more profound parallels.
In Elden Ring lore, the Erdtree guides the souls of the departed, explaining the catacombs at its base. Interestingly, Nuytsia holds similar spiritual significance in Australian Aboriginal culture, its blossoms representing the souls of the deceased, their vibrant hues echoing the sunset, the perceived destination of spirits.
Further strengthening the comparison is Nuytsia's semi-parasitic nature; it sustains itself by drawing nutrients from neighboring plants. This resonates with a prevalent fan theory positing the Erdtree as a parasite, having usurped the life force of a primordial Great Tree. However, it's now understood that game descriptions referencing a "Great Tree" are mistranslations, actually referring to the Erdtree's own extensive root system.
Ultimately, whether these striking parallels between Nuytsia and the Erdtree are deliberate design choices or coincidental remains a mystery known only to FromSoftware.