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| Sequoiadendron giganteum - Mammoth Tree |
Sequoiadendron giganteum commonly known as Mammoth Tree also
called Big Tree or Wellingtonia is the largest and long living tree. The
Wellingtonia provides the largest tree in the world – over 50,000 cubic feet
(over 1,000 tons) in the Sequoin National Park in the Sierra Nevada of
California. It lives for upwards of three thousand years, yet it is second in
longevity to the scruffy, distorted Bristle-cone Pine, Pinus aristata Engelm.
Many people will recall the Wellingtonia as the tree through which one could
drive a car! Its native habitat is now some seventy isolated groves at between
five thousand feet and eight thousand feet amid the sierras of northern California,
where many of the trees stand as huge orange-colored columns perplexing the
imagination and almost defying the skill of the photographer. The tree was
first introduced into Europe in 1853.
The world's largest single trees and largest living thing by
volume. Giant sequoias grow to an average height of 50–85 m (164–279 ft) and
6–8 m (20–26 ft) in diameter. Record trees have been measured to be 94.8 m (311
ft) in height. Claims of 17 m (56 ft) diameter have been touted by taking an
author's writing out of context, but the widest known at chest height is closer
to 8.2 m (27 ft). The young shoots
remain covered by the needles (more correctly, leaves) for three or four years.
The minute scale less buds are hidden by the foliage. The needles are lance-shaped
‘scales’ which completely clothe the twigs, with a four-pointed tip, and when
crushed have a minty smell.
Both sexes of flowers are on the same tree, the small
club-shaped yellow males in clusters at the twig tips, and the pale green
globular females, bearing spine-tipped bracts, further back. The cones are
egg-shaped, made up of thick flat-surfaced green scales which do not overlap.
They swell to 2.5 – 5 cm long, becoming reddish-brown, and mature in the second
autumn, releasing winged seeds. Many of the empty cones persist on the tree for
indefinite periods.
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| Sequoiadendron giganteum - Mammoth Tree |
The fibrous bark is reddish-brown (‘fox-red’) to
blackish-brown or grey, soft and spongy, becoming very thick and deeply fluted
with age. Underneath is an inner layer that is thin and firm. Where side
branches have fallen away, distinct cavities are left in the bark. The tree is
conical in shape, with a tapering and broadly buttressed trunk, and with
drooping branches and a narrow crown. The wood has a thin zone of pale yellow
sapwood, and a reddish-brown heartwood. It is soft, strong, and naturally
durable; when from time to time and individual tree is felled the wood is used
for general planking, posts and garden furniture.
The towering Wellingtonia is conspicuous as an avenue and
park tree, and stands out un-mistakenly in the distant landscape. A few groves
as at Westonbirt in Gloucestershire, indicate that the tree might be successful
in European country in plantation form, but in general silviculturists have not
planted it, perhaps chiefly on count of the high cost of plants.
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