Deterrence!
編集者: chuchutrain
The helicoradian is a part-plant-part-animal life form; because it couldn’t move freely on its own, it possesses ridiculously swift reaction which protects it from danger. Moreover, other creatures inside the forest relied on the helicoradian to warn them about nearby dangers! If any small animal were to fall into their leaves, it would swiftly retract; trapping the small animal inside and digesting it for additional nutrients.
Of course when Na’vi clans required garments or sacks, they utilized the leaves of the helicoradian as an absolutely excellent raw material. If they wanted to weave ornate ceremonial robes or garments, they would kill off a hexapede*, and bury it beneath the roots of the helicoradian; it then would require only a week for the leaves to wither up.
(TN:* A hexapede (Na'vi name: yerik) is a land herbivore that resides in the various biomes of Pandora, including rainforests, savanna, subarctic tundra, and mountainous regions.)