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The Giant Sequoia

The Giant Sequoia

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The Giant Sequoia

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  1. The Giant Sequoia

  2. "Walk in the sequoia woods at any time of year and you will say they are the most beautiful and majestic on earth. Beautiful and impressive contrasts meet you everywhere, the colors of tree and flower, rock and sky, light and shade, strength and frailty, endurance and evanescence"(John Muir)

  3. What is Sequoia? • Giant sequoia (Sequoiadendron giganteum), or "bigtree" as it is often called, is among the largest and oldest of living organisms. While taller trees do exist, including its closest of kin the coast redwood, no species of tree matches its girth, and only a few species of any type manage to survive longer than these colossal giants. While the oldest accurate account of the age for a giant sequoia is 3200 years, it is suspected that specimens have survived for as long as 5000 years.

  4. Today giant sequoia grows in only 75 scattered groves in California, where it earns its name as "the sentential of the Sierra." These groves exist in a 260 mile stretch of the Sierra Nevada mountains, typically from 4,500 to 7,500 ft. in elevation. In total there are only 35,600 acres of forest where giant sequoias make their home. • The lack of evidence of these trees elsewhere in the Sierra suggest that the distribution of the bigtrees has been relatively unchanged since the most recent retreat of the glaciers. Fortunately most of the giant sequoia groves are now protected on both public and private land, hopefully assuring their permanence in their delicate mountain ecosystem.

  5. Old sequoias average between 10 and 15 feet in diameter, and between 250 and 280 feet in height. Some of the most ancient trees, though, have attained heights more than 330 feet and diameters more than 35 feet. Several of the most spectacular trees have even been named. These include the "General Grant", the "Grizzly Giant", and perhaps the most massive and famous all, the "General Sherman" tree in Sequoia National Park.

  6. Generally accepted as the largest single living organism on earth, the General Sherman tree is 30 feet thick at shoulder height, and 17 feet thick at a height of 120 feet. The first branch of the tree is more than seven feet in diameter, and the tree itself towers to a height of 275 feet. While not all giant sequoias are as famous as the General Sherman, a walk through any of the bigtree groves will make all other trees, as well as yourself, seem miniature by comparison.

  7. The pointed leaves of giant sequoia are short, generally between a quarter and a half inch long, and are a majestic blue-green in color. The leaves turn brown and die after their second or third season, but persist on the tree for several more years. • When the leaves are shed, they fall still attached to the twig, similar to all members of the redwood family. The steady loss of large amounts of foliage creates a thick litter bed under large giant sequoias. Unfortunately, heavy foot traffic under the trees can still damage the fragile root system of giant sequoia. While the roots of an ancient tree may extend as far as 200 feet from the trunk, water is absorbed by tiny fibrous roots which are often near the surface. Disturbance of the forest litter will often kill these roots, ultimately harming the health of the tree.

  8. The cones of giant sequoia are similar, but larger than those of redwood. While those trees grown in the open, or in nurseries, may begin bearing cones as young as age 10, most giant sequoias in the forest do not begin to produce large cone crops until they are nearly 200 years old. The woody cones of giant sequoia are two to four inches long, and are approximately egg-shaped. Cones reach their full size in their first year, but require a second year to mature. Cones tend to persist on the tree, often remaining closed for as many as twenty years, before releasing their tiny seeds.

  9. Not surprisingly, giant sequoias are fast growing trees, averaging approximately 2 feet per year in height. The growth rings of this young tree are testament to the rapid diameter growth of the trees as well. In general, a giant sequoia will grow rapidly until it attains a height of about 200 feet. At this point vertical growth begins to slow or even stop, but growth of the trunk continues. In a single year a tree like the General Sherman adds enough wood in the form of diameter growth to be equivalent to a tree a foot and a half in diameter and 60 feet tall.

  10. Despite their large size, and rapid growth characteristics, giant sequoias are no longer cut for timber. The wood, which is extremely resistant to decay, is also very brittle, and is frequently destroyed in the falling process. Several groves of giant sequoias were all but destroyed shortly after their discovery in the mid-nineteenth century. In general though, the species never became important industrially because it was so difficult to harvest. Today almost all giant sequoias are protected from cutting, helping to minimize the threats humans pose to their continuance.

  11. "A sharp reminder hits me: this world is alive; it stretches out there shivering toward its own creation, and I'm part of it. Even my breathing enters into the elaborate give-and-take, winter, summer, storm, still-this tranquil chaos that seems to be going somewhere. This wilderness with a great peacefulness in it. This motionless turmoil, this everything dance.“ (William Stafford)

  12. Web sites • http://www.giant-sequoia.com • http://library.thinkquest.org • http://en.wikipedia.org/wiki/Giant_Sequoia_National_Monument