Lianas are long, woody vines that typically grow in tropical rainforests. They use trees and other structures for support, climbing towards sunlight. Lianas can reach impressive lengths and are often found intertwined with other plants, contributing to the dense vegetation of their habitat. These plants play a crucial role in the ecosystem by providing food and shelter for various animals, including birds and insects. Lianas also help in stabilizing the forest structure and can influence the growth of surrounding trees by competing for light and nutrients.