Meadlin's tree were the large species of fungus on Nyriaan and could grow to be up to sixty meters tall, although some specimens in the planet's unexplored regions were reported to be twice that height. Meadlin's trees grew in groups and and would twist around each other and merge as they got bigger, forming complicated networks that were several kilometers in length. These outcroppings also produced a dim blue light, which was emitted from the trees' spherical spore buds.
The largest networks of Mealin's trees grew inside Nyriaan's caverns and canyons. The native Nyriaanans often lived inside these networks and would take care of the trees, guiding their growth so that their branches formed defensive emplacements.