Top 10 trees facts

4 meters (13 feet). The sequoias root system is wide spreading, but shallow. There is no taproot. A mature sequoia's roots can occupy over 1 acre of earth and contain over 90,000 cubic feet of soil.

The soil. The permafrost prevents trees from developing a deep root system. Climate variations or forest fires can thaw the upper extents of the permafrost, creating a ground slump called thermokarst.

Lignins are particularly important in the formation of cell walls, especially in wood and bark, because they lend rigidity and do not rot easily. Chemically, lignins are cross-linked phenolic polymers. Lignin constitutes 30% of non-fossil organic carbon and 20 to 35% of the dry mass of wood.

Traveller's tree. Ravenala, commonly known as traveller's tree is a palm resembling tree native to Madagascar. At the top of the tree are banana-like leaves, with pale midribs that give a fanlike appearance. It is named so because the water it accumulates in its leaf bases can be used in emergencies for drinking. However, the water inside the plant is murky, black and smelly and should not be consumed without purification.

Eucalypts. Eucalyptus regnans, the Australian mountain ash, is the tallest of all flowering plants. Today, the tallest measured specimen named Centurion is 99.6 m (327 ft) tall (taller than the highest giant sequoia). Six other eucalypt species exceed 80 metres in height.

The sandbox tree. Hura crepitans, the sandbox tree, also known as possumwood and jabillo, is an evergreen tree of the spurge family (Euphorbiaceae), native to tropical regions of North and South America, including the Amazon Rainforest. It has also been known as the Dynamite tree, so named for the explosive sound of the ripe fruit as it splits into segments. This tree prefers wet soil, and partial shade or partial sun to full sun. It is often cultivated for shade.

Water storage. The swollen trunk of the baobab tree can store as much as 31,700 gallons (120,000 l) of water to endure harsh drought conditions. Indigenous Australians used baobabs as a source of water.

Siberian larch. In Sibrerian Taiga permafrost occurs and restricts root growth. Trees are therefore prone to windfall.

Manchineel. The manchineel tree is native to tropical southern North America and northern South America. All parts of the tree contain strong toxins and even the merest contact with human skin causes a breakout of blisters, and blindness can occur if it touches a person's eyes. In some parts of its range, many trees carry a warning sign, while others are marked with a red "X" on the trunk to indicate danger.

Fire. Young sequoias are able to grow successfully only in mineral soils in full sunlight, free from competing vegetation. They therefore require periodic wildfire to clear the area. Due to very thick bark, the fire doesn't harm sequoia.