Colossal Trees are a rare phenomenon: trees that grow extraordinarily fast and without limits. Though almost always true trees, it is hypothesized that any plant could become Colossal. A Colossal Tree can easily have a trunk several miles around and a height that stretches to the edge, or even beyond, of the atmosphere. A Colossal Tree generally constitutes a Province in itself, though younger specimens may not be large enough, and some trees - palms, for example - may simply not support enough life for that. Ecosystems adapted for life in Colossal Trees are called arboreal, and sentient arboreal species include specially adapted versions of almost any race, some of whom live in or on the trunk, branches, leaves, flowers or roots, depending on the tree and species in question. Larger and more populous Colossal Trees may constitute a Region, or even a Setting in some circumstances.
Colossal Trees are exceedingly uncommon, however, there is a cluster of them called the Great Grove. It contains several dozen Colossal Trees in a circle, with one tree, a Colossal yew, in the center. The Great Grove was created by a long-ago Deity who was well-known in several Colossal Trees, using several dozen of the most common species.
By extension, anything so much larger than a common specimen of its type may be termed "colossal" if it is a Province or larger unit, but the Colossal Tree remains by far the most common example of this phenomenon.
List of Colossal ecosystems
- The Great Grove is excluded.