#101-10-2010, 04:08 PM
أعلى شجرة في العالم اكتشفت عام 1872 في أستراليا و هي من نوع اوكاليبتوس ، وبلغت 152 مترا. أما حاليا، فإن أعلى شجرة هي من نوع السكويا في كاليفورنيا وتبلغ 112 مترا، وهذا النوع من الأشجار قد يصل طوله إلى 140 مترا أحيانا. ثم يليه شجر الصنوبر دوغلاس الذي يعيش في الولايات المتحدة ويصل إلى 94.5 م. و أقصر شجرة هي من نوع الصفصاف العشبي الذي يعيش في المناطق القطبية ولا يزيد علوّها عن 2 سنتم.
أنها أشجار السكويا ,, أو شجرة الخشب الأحمر العملاقة RED WOOD TREE :
السكوبا أو الخسب الاحمر : شجرة عملاقة تُعد من بين أكبر وأقدم الكائنات الحية التي تعيش على ظهر الأرض، حيث نمت منذ ملايين السنين في غابات كبيرة في كل مكان من العالم. وكان يوجد منها أنواع كثيرة مختلفة، ولكن لم يتبق سوى نوعين اثنين من السكّويا الحقيقية، بالإضافة إلى شجرة أخرى صينية قريبة الصلة بهما. وهذان النوعان الحقيقيان، هما: الشجرة الجبارة، والسّكويا العملاقة، ويوجدان بصورة رئيسية في ولاية كاليفورنيا بالولايات المتحدة الأمريكية. ويرجع اسم السكويا إلى أحد هنود الشيروكي الذي اخترع ألفبائية للكتابة لقبيلته.
تنمو الأشجار الجبارة، والمسماة أيضًا بشجر الخشب الأحمر الساحلي، أو أشجار كاليفورنيا الحمراء على الجبال المطلة على ساحل المحيط الهادئ من منتصف ولاية كاليفورنيا حتى جنوب ولاية أوريجون. وتزدهر الأشجار هناك، حيث يكون المناخ دافئًا نسبيًا ورطبًا.
تعتبر الأشجار الجبارة أطول الأشجار الحية، حيث تنمو حتى ارتفاع أعلى من 90م، أو ما يعادل ارتفاع مبنى مكون من 30 طابقًا تقريبًا!!!!. ويمكن لجذورها أن تمتد إلى عمق 45م!!! من سطح الأرض. وقد يصل قطر جذوع العديد من الأشجار الجبارة إلى أكثر من 3م.
يتراوح سُمك قلف أشجار السّكويا العلوية ما بين 15 و30سم، ويتميز بأخاديد عميقة، يتراوح لونها بين البني المحمر والبني القرفي. أما لون الخشب، فأحمر صاف فاتح، وعندما يتعرض الخشب للعوامل الجوية، يتحول إلى الأحمر الداكن. ويمتاز خشبها الخام بالمتانة والقيمة. ويمكن للشجرة الواحدة أن تعطي كمية، قد تصل إلى 1,130م§ من الخشب الخام. !!!!!!!!
Tallest tree in the world: coast redwood
The coast redwood, the world's tallest tree, is one of
the three sequoia tree species, together with the giant sequoia (Sequoiadendron giganteum) and the dawn redwood (Metasequoia glyptostroboides). The coast redwood (Sequoia sempervirens) grows in natural stands in a long, thin coastal area along the Pacific Ocean in the west and northwest of the US (mostly California). It is the tallest tree in the world.
With its relatively slender silhouette this tree can grow even 20 meters higher than the tallest giant sequoias, that are nevertheless the biggest trees in the world, when looking at the volume of the trunk. The tallest known living tree, named Hyperion, is 115.55 m or 379.1 feet (measured in 2006) tall! This gets close to 120 to 130 m, that, according to a 2004 biological study, is the maximum attainable height  of a tree.
Foggy coastal forests of the Pacific
During the whole year it rains quite a lot in this thin coastal strip and it is quite foggy most of the time. This way the tree can absorb enough water and does not suffer that much from evaporation stress. Most of the tallest trees can be found in the wet river valleys on fertile, alluvial deposits, although unexpectedly a couple of recently discovered record breaking trees appeared to grow on the valley slopes. The coast redwood forests have an abundant undergrowth (amongst which there are a lot of ferns). However, the biggest biodiversity can be found tens of meters up: differents species of plants, lichens, salamanders, ... live high up in the sky between the complex branch systems of the redwoods. Prof. Steve Sillett, who studies these redwood canopies, compares them with "hanging gardens".
The get an impression of the size of these redwoods: the images above show some of these trees. On the left is the "Del Norte Titan" in the Jedediah Smith Redwoods State Park, California (© Bob Van Pelt). Notice the people in the left bottom corner. The tree on the right is called "Screaming Titans", also in Jedediah Smith Redwoods State Park.
The Del Norte Titan has a height of 93.6 m and a girth at breast height of 22.7 m. He is definitely not the tallest coast redwood, or the thickest, but has the second largest trunk volume ("The Lost Monarch" comes in first, depending on your definition of a "single tree"). Nevertheless he is surpassed in volume by the giant sequoia (Sequoiadendron), of which about fifteen specimens have a bigger volume with "General Sherman" on top of the list.
On first sight, the needles of the coast redwood do not resemble those of the giant sequoia: they are bigger and flat, much like that of a yew. The crown is conical just like the one of the giant redwood, with an almost equally massive trunk with a reddish brown, soft bark. The egg shaped cones are smaller (2 to 3 cm). In contrast to most other conifers, the coast redwood starts to grow again after being cut. The maximum age is probably around 2500 years.
Heavily threatened by logging companies
This quickly growing tree has straight trunks and the quality of the wood is excellent, which resulted in heavy - and ongoing - loggings. The wood of Sequoia sempervirens has been and is extensively used in construction. About 96% of the original redwood forests have been logged and the deforestation is still continuing. Luckily most of the few remaining stands are preserved in the National and State Parks, which are probably essential for the long term preservation of this species.
The woods outside of the parks (with many trees more than a thousand years old) are still being "commercially managed".... This is source of constant protests, such as the famous action of activist Julia Butterfly Hill (photo). For over two years, she lived in the canopy of a coast redwood named "Luna" to keep the the old growth tree from being logged by the Pacific Lumber Company and to plead for sustainable forestry instead of clearcutting entire woods (which has devastating effects on the natural balance and causes extreme soil erosion). Eventually she succeeded: as a result of the massive press coverage (and the attention for the old growth forest clearcuttings it brought with it) "Luna" and some other redwoods were saved from the chain saw. What a remarkable woman!
It's highly probable that without actions like that and protests of organisations like "Save the redwoods League", "Sempervirens Fund", "Sierra Club", and others, there would be no old growth redwood forests left. These organisations get their money from gifts and buy privaty property themselves to donate them to the State Parks and National Parks.
The images below were taken by Nick Sabadosh in the misty redwood woods near Crescent City, California an are used here with permission . These holiday photos show specimens of Sequoia sempervirens in their natural environment, the foggy forests near the Pacific.
Because of the dramatic atmosphere, these forests have been used as scenery in movies: the scenes with the Ewoks in the Star Wars movies were shot in these woods, just as multiple parts of the Jurassic Park movies. For those last movies this choice is not very unlogic: during the Cretaceous, the top period for North American dinosaurs, these woods could be found all over the continent.
These trees (and especially young ones) are quite sensitive for winter frost and do not grow that well on the eastern side of the Rockies and in most parts of Europe. Biggest limiting factor is drought: it just isn't wet enough. In the wettest European parts, in England and Wales, planted redwoods do already reach 45 meters and more en seed themselves.
Most of the groves are located in the coastal area of California. The largest populations are in Jedediah Smith Redwoods State Park (Del Norte County), Redwood National Park and Humboldt Redwoods State Park (Humboldt County).
The most visited grove is in Muir Woods National Monument, one of the last remaining stands in the immediate San Francisco Bay Area. The tallest tree in the world
Hyperion, the world's tallest living tree, is a coast redwood and is no less than 379.1 ft (115.55 m) tall!
This enormous tree was discovered only in August 2006 in a remote part of the Redwood National Park, California.
Sequoia sempervirens (D. Don) Endlicher 1847.
Synonynms Taxodium sempervirens D. Don in Lambert 1824 (Watson 1993), Sequoia sempervirens (Lambert) Endlicher (Peattie 1950). It is the only species in the genus Sequoia Endlicher 1847. Horticultural varieties (cultivars) have been selected, like 'adpressa', 'glauca', 'nana pendula', 'pendula' en 'prostrata'. More record trees
The World's Tallest Tree: A Redwood
First posted Octrober 2, 2006 Last updated October 2, 2006
From the SF Chronicle, September 29, 2006
Researchers have confirmed that a 379.1-foot tree in Redwood National and State Parks is the world's tallest -- a foot higher, even, than originally thought. And the naturalists who discovered the tree say it's unlikely that they'll find a taller redwood. The tree, which the discoverers named Hyperion, displaces the Stratosphere Giant, a redwood in Humboldt State Park, as the world-record holder. Two other recently-discovered trees in Redwood National Park have also measured taller than the 370.5-foot Stratosphere Giant. Although researchers took laser measurements of all three of the redwoods this summer, final measurements had to wait until the end of the marbled murrelet's nesting season. The endangered seabird broods in old-growth conifers.
About two weeks ago, one day after the murrelet nesting season ended, Humboldt State University forestry Professor Steve Sillett climbed Hyperion and dropped a measuring tape to the ground. Sillett, who specializes in the ecology of ancient forest canopies, has received global attention for both his academic work and his prowess in scaling the world's tallest living organisms. Climbing the world's tallest tree to the top was no small feat, said Michael Taylor, an amateur naturalist who, with partner Chris Atkins, discovered the three trees this summer. Sillett used a powerful crossbow to shoot a bolt with a trailing line over a limb about 250 feet up the redwood's trunk. The line was fixed to a rope, which was pulled over the limb and anchored to a nearby tree. Sillett and three other climbers ascended the rope into the canopy. Chances of finding a tree that could best or even equal the new champ are remote, Taylor said. "Between us, Chris and I have already covered about 95 percent of the prime habitat for big redwoods," Taylor said. "There aren't too many more places we could look." Hyperion, which may be 700 to 800 years old, could have been taller but for woodpecker damage at the top. "It's possible it could've topped out at 380 feet," Taylor said. Four decades ago, there were thousands of trees Hyperion's size, but they were logged along with more than 90 percent of the state's ancient redwoods. "Thirty years ago, they were cutting in 24-hour shifts (in the basin where Hyperion is located), using headlamps at night," Sillett said. The only thing that saved Hyperion, Sillett said, is the expansion of Redwood National Park in 1978, just before the remaining giants were wiped out. Sillett said redwoods can't reach Hyperion's the lofty heights unless they are protected from wind. In the original old-growth coast redwood forests, the giant trees themselves comprised the windbreak. A universal constraint on tree height is getting water up the trunk and to the treetops. Sillett said the tallest tree reliably recorded was a Douglas fir in British Columbia's Lynn Valley, measured in the late 19th century at 414 feet.
"We don't have a generalized limit on tree height yet because it can vary greatly depending on soil and climate," Sillett said. "But our research indicates (the Lynn Valley fir) may be close to the limit."
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#201-10-2010, 04:17 PM
#301-10-2010, 04:33 PM
#401-10-2010, 04:37 PM
World’s Tallest Living and Oldest Teak Tree – Kannimari Teak, India
Another amazing tree in India is a banyan tree that stands in the Indian Botanical Gardens in Howrah. This 200 year-old tree is considered as the world’s largest banyan tree, with a circumference of approximately 330 meters. It was really incredible. This single tree looks like an entire forestThe Tingle Tree – Australia
There’s only one place where you can find the red tingle tree in the world – Walpole-Nornalup National Park, Australia. They are the largest of all the eucalyptus with a girth of up to 26 meters. Growing up to 75 meters tall these trees, can live to over 400 years old.
World’s Largest Teak Tree – Thailand
The tallest and oldest teak tree in the world is the Kannimari teak in India but the largest teak tree in the world is the Big Teak Tree Forest Park in Nam Pat District, Uttaradit. It has an approximate age of 1,511 years, measuring 37 meters in height and 6.57 meters in diameter.
Largest Ginkgo – Japan
The world’s largest ginkgo is located in Sarukawa No Ichou. It is 50 meters tall with a girth of 11.2 meters. This ginkgo is about 1,000 years of age and one of the tallest in Japan.The Senator – Largest Bald Cypress in the USA
The Senator is the largest Bald cypress tree in the United States. It is 35 m (115 ft) tall, with a trunk diameter of 344 cm, and an estimated stem volume of 119.4 m3. It is located in Big Tree Park, Longwood, Florida, and as of 1993, is estimated to be 3500 years old.Largest Eucalyptus Tree in the US
The largest eucalyptus tree in the US is in Fort Ross Park World’s Largest Cryptomeria – Jomon Sugi Tree – JapanGloucester Tree – Australia
Jomon Sugi is a very large tree located on Yakushima Island, Japan. It is Japan’s national tree. This large “Yakusugi Cedar” (Cryptomeria japonica)tree was located in 1996 and has since become quite famous. It is said to be the largest specimen of Cryptomeria known. It is 25 meters tall and estimated to be around 2,200 years old. It is called “Jomon-sugi” (meaning Old Cedar though it’s not a cedar) and is located in the Yakushima World Heritage Area.
Looking for some adventure and fun and want to experience climbing some of the highest trees in the world? A giant karri tree in the Gloucester National , Australia called the Gloucester tree is the tallest fire-lookout tree in the world. The Gloucester tree has a height of 61 meters or 201feet. Visitors can climb up to a platform in its upper branches for a spectacular view of the surrounding karri forest.World’s Largest Cashew Tree – Brazil
Have you seen the largest cashew tree in the world? The largest cashew tree in the world is found in Brazil. The tree covers an area of about 7500 square meters, with a perimeter of about 500 meters.The Square Knot Tree