The giant sequoia (Sequoiadendron giganteum), the biggest tree in the worldThe name giant sequoia or giant redwood as well as its scientific name Sequoiadendron giganteum indicates clearly what's remarkable about this tree: it's giganteum - gigantic.
Specimens of these giant conifers in their natural range, the Sierra Nevada range in California, are true giants. The image on the left is an example: the base of the trunk of an old growth giant sequoia in Sequoia National Park, California can be seen. Notice the woman sitting on the right.
The "General Sherman" tree, the biggest amongst them, has a circumference near the ground of 31.1 m or 102.6 ft and is the biggest tree in the world. Its age is estimated at 2000 to 2500 years, and the tree is often called "the largest living thing on earth".
Although Sequoiadendron giganteum is the biggest tree in the world when looking at the volume of the trunk, the tallest tree in the world is a specimen of the coast redwood (Sequoia sempervirens), a close relative of the giant sequoia.
Since their discovery in mid 19th century, giant sequoias have been planted as ornamental specimens everywhere around the world. Especially in western Europe, where the oldest ones (since 1852) are found, they grow vigourously: the tallest ones are already more then 54 m tall (177 ft) and the circumference of the thickest ones already exceeds 11 m (35 ft).
DescriptionThe giant sequoia is an evergreen conifer, with a typical reddish brownish soft thick bark.
The tree has a large, relatively thin, conical crown. The upper branches are upright, while the lower ones are hanging down with upright tips. Younger trees (up to 10 m tall) do not have these "hanging" branches and have an almost perfect conical crown. The top of older trees gets more and more rounded over time. The drawing on the right shows a typical 120 to 150 years old planted specimen.
The trunk has a wide base, and gets thinner after a couple of meters. The strikingly soft, fibrous bark can be punched easily with the fist, which explains its nickname in a number of European countries: the boxing tree. The quality of the wood is rather low (especially in older specimens) so the species is of no importance in forestry.
The needles are small and are more scale like. They cover the branches completely. The needles never drop by themselves, always a number of branches fall down together after they die as a result of, for example, drought or shading.
Also the egg shaped cones are not that big (4 to 5 x 3 to 4 cm, roughly 2 by 3 inches), but can contain hundreds of small, light seeds of 3 to 4 mm length.
Natural rangeThe giant sequoia has natural stands in a long, narrow strip of about 300 km (200 miles) length on the western slopes of the Sierra Nevada range in California, United States. They grow at altitudes of 900 m to 2440 m, where there can be quite a lot of snow in winter. Most of the groves of giant sequoia are part of the National Parks or State Parks system of the U.S.
Only discovered in 1852 during the Californian gold rush, then off to European estate gardensDuring the second half of the 19th century it was fashionable for European castle and estate lords to lay out a so called English garden (also called a garden in landscape style). These gardens, influenced by Romanticism, were gardens consisting of apparent wild parts, winding paths and an abundance of plant species.
As soon as the forests of giants were discovered in the Californian mountains during the gold rush (in 1852), the giant sequoia became a very fashionable tree to plant in these gardens, that were often constructed as arboreta with lots of exotic, recently discovered tree species. This explains why the oldest specimens outside their natural range can be found in European castle gardens and arboreta.
Growth in the UK is very fast, especially in Scotland where some specimens already reach 54 m (177 ft). The stoutest is 3.55 m (11.65 ft) in diameter.
These are the tallest giant sequoias outside California. They can be found in the beautiful botanic garden of Benmore, Argyll, Scotland. This avenue was planted in 1863 and contains about fifty trees of which the tallest is now 54 m tall. Most of them are between 50-53 m tall and they are still growing rapidly.
The nameThe name "Sequoia" derives from the Cherokee native American Sequoyah (c.1767 - 1843), who developed a writing system for his people. This way he wanted to preserve the Cherokee culture, that was under heavy stress by the influence of the western civilisation. Thousands of native Americans learnt to write in this alphabet, that is still used by the way.
When in 1847 the coast redwood (Sequoia sempervirens) was botanically described for the first time, the botanist Endlicher chose the name Sequoia, but he did not give any explanation about why he picked that name. But it is now generally agreed that he choose the name in honour of Sequoyah, who's syllabary was quite popular at the time. When later the giant redwood was discovered, there were some troubles about the scientific name to be used, but eventually Sequoiadendron was chosen.
In Great Britain the tree is commonly known as the Wellingtonia, named after the duke of Wellington who died the year before the official discovery of the species.
Growing your own redwoodIt is possible to grow your own giant redwood tree from seed.
Scientific classificationThe giant redwood, Sierra redwood, giant sequoia, Wellingtonia, big tree or Sequoiadendron giganteum belongs to the cypress family, the Cupressaceae, order Pinales, to which for example also the bald cypress belongs.
Within this family the giant sequoia forms, together with the two other types of sequoia, the subfamily Sequoioideae.