Violet fungus

Violet fungus was a type of fungus that grew up to 7' (2.1m) high.

Variants
Cormanthorian violet fungus grew only to around 3' (0.9m) high. It was often used by treants who would surround their roots with up to six of these fungi. The fungi's roots tapped into the treant for sustenance, and they helped to protect it against bark-eaters by flailing with tentacles, attempting to rot the predator's flesh.