The Fountain Tree is a relatively small rainforest succulent that has a deep root structure and a slim trunk which is crowned by densely leafed branches terminating in bulbous, fluid-filled fruit.
The balloon-like fruit are slowly filled with moisture drawn from the ground and fill until internal pressure causes them to burst, drenching the surrounding ground and roots with nutritious fluids and newly dispersed Fountain Tree seeds. This process is ongoing, with new fruit quickly replacing any that have burst.
The fountain tree is highly sensitive to local environmental conditions, which can be most clearly seen in its fluid-filled fruit and the liquids they contain.
Na'vi use the fountain tree as a barometer of local forests health, which in turn helps experienced hunters and foragers predict what they can find nearby. Although not drinkable, the taste of a burst fruit's fluid reveals a lot about the soil, animal life and vegetation growing nearby. For instance, a sharply sweet fluid means that the tree is rarely disturbed by herbivores and edible plants can be expected. Bitter, soil-like taste means the area is within the hunting ground of a carnivore.