Which tree has an extensive root system, growing in large colonies, derived from a single seedling?

The Aspen is a tree that has an extensive root system called rhizomatic, a modified subterranean plant stem that sends out roots and shoots. This feature results in most aspens growing in large colonies, derived from a single seedling, and spreading by means of root suckers. New stems in the colony may appear up to 30-40 m or 98-131 feet from the parent tree.

Each individual tree can live for 40-150 years above ground, but the root system of the colony can in some cases live for thousands of years, sending up new trunks as the older trunks die off above ground. For this reason, aspens are considered to be an indicator of ancient woodlands. One such colony in the western state of Utah in the United States was given the nickname of 'Pando', estimated to be 80,000 years old.

Recently aspen populations have been declining in some areas possibly due to climate change such as droughts and changes in precipitation patterns.

Young aspen bark is an important seasonal forage for the European hare and other animals in early spring. Aspen is also a preferred food of the European beaver, elk, deer and moose- not only do they eat the leaves but they also strip the bark with their front teeth.

Aspen wood is white and soft, but fairly strong, and has low flammability. It has a number of uses, notably for making matches and paper where its low flammability makes it safer to use than most other woods.