Ubertubers are currently the largest known species of sentient root. At maturity, the average plant has a mass equal to that of five elephants. Based on available data, it is believed that an Ubertuber's life-span is between 700 and 900 years.
Despite having consciousness, the tuber will spend most of its life in a vegetative state, passively absorbing nourishment from the environment. Only in times of emergency do the colossal plants become active, uprooting themselves for self-defense: e.g. when threatened by a forest fire, logging, or mining operations.
When awakened, the Ubertuber seeks immediate escape. If necessary, it is a fearsome foe -- tearing down trees and wielding them as weapons. Once it gets away from what threatens it, the plant will walk several hundred miles to find a suitable new home.
The root is semi-parasitic. It derives minerals and water from the soil -- but for certain nutrients, it taps into the trees around it. Consequently, one of the best ways to find an Ubertuber is to search a forest of great old tall trees for a patch where the trees are mysteriously shrunken and shriveled.
Ubertubers reproduce asexually by means of spores, which are released into underground streams. The reproductive cycle is usually triggered by flooding, when the water table is especially high. Given that Ubertuber populations are able to expand subterraneously, we currently have no clear idea how geographically widespread the plants are, or how many exist.