Giant sequoia, king of all conifers
If a Tyrannosaurus rex peeked out from behind one of these trees, the famous dinosaur would be dwarfed.
Thu, Jul 08, 2010 at 10:02 AM
John Muir — 19th century author, naturalist and founder of the Sierra Club — called the giant sequoia “the noblest of a noble race” for many worthy reasons.
These exquisite specimens date back to at least 150 million years ago to the Jurassic Period — a time when the great plant-eating dinosaurs ruled the land and the ocean was stocked with ichthyosaurs and the long-necked plesiosaurs.
Magnificent giant sequoias once thrived from Alaska to the Midwest, from Europe to the Orient and even in Greenland.
The big trees, as they are affectionately known, have survived epic geologic upheavals and extreme climate changes. As a matter of fact, on Specimen Ridge in Yellowstone National Park in Wyoming, a fossilized 26-foot sequoia stump juts up amongst 40 million-year-old volcanic debris.
About 18 million years ago, the remaining giant sequoia populations mostly occurred in southern Idaho and western Nevada. As the climate cooled and continued to dry out, giant sequoias were forced to migrate southwest. They expanded their range west into California before the Sierra Nevada range became the formidable backbone of the state. The mountains cut off any moisture, and the eastern population of big trees perished.
When early settlers discovered these colossal trees, they senselessly felled and abandoned them because they were simply too big and too costly to handle. To give some idea of their stature, it took four men working 22 days to fell one tree. Muir persuaded newspaperman Col. George W. Stewart of Visalia, Calif., to protect them.
Today, they are one of the rarest tree species in the U.S. and are scattered in about 75 groves occupying 39,500 acres, ranging in elevation between 5,000 and 7,000 feet above sea level along a 250-mile stretch of the western Sierra Nevadas.
In order for these gargantuan trees to survive — especially during the hot dry summers — they require at least 60 inches of precipitation, which mostly occurs from November to April as accumulated snowfall. It’s not uncommon for a 16-foot snowpack to sit on the ground. It’s this accumulated snowfall that provides California — the eighth-mightiest economy on the globe, the most intensive agriculture system on Earth, and 38 million residents and millions of tourists each year — with 90 percent of the state’s water.
So just how big do these giant trees get? If a Tyrannosaurus rex sauntered from behind a giant sequoia, even it would be dwarfed.
These rich, cinnamon-barked beauties can easily attain 280 feet in height with a 29-foot diameter. One giant sequoia may contain more wood than an entire old growth Eastern hardwood forest can grow in 2 acres.
Sequoia shares name with developer of Cherokee language
Even the name sequoia is steeped with history. Sequoyah was a brilliant Cherokee Native American who developed a written version of his people’s language. Its present botanical name, Sequoiadendron giganteum, translates to “the giant sequoia tree.”
In addition to possessing an astounding trunk at its base, this species exhibits very little taper as it grows toward the heavens. For instance, many old trees retain their first branches at 120 feet above the ground — diameters of trunks this high off the ground easily exceed 16 feet. And, sequoias can live for at least 3,200 years, meaning they would witness more than 1.1 million sunrises.
All the ancient trees have been named. General Sherman lives in Sequoia National Park and he’s an awesome specimen — the undisputed heavyweight champion of the tree world.
General Sherman is the largest single-stemmed tree on Earth: 274.9 feet tall, circumference at the ground is 102.9 feet, diameter at the base is 36.4 feet, 110 feet above the ground his diameter is an astonishing 17.4 feet. The first branch occurs 129.9 feet off the ground or the equivalent of a 12-story building, and it’s 7.2 feet thick, rising another 127.9 feet into the sky.
The roots occupy 91,500 cubic feet of soil and the trunk holds over 138,000 gallons of soil water.
General Sherman is about 2,400 years old, yet it's the fastest growing tree on the globe, adding the equivalent radial wood of a tree 1.5 feet thick and 62 feet tall each year!
The ecology of giant sequoias is fascinating. They have evolved with fire, 2.5-feet-thick bark loaded with tannic acid; the same chemical used in fire extinguishers worldwide helps protect mature trees from surface fires. The fire exposes the mineral soil for falling seeds to germinate.
A feast for squirrels
Douglas squirrels can cut up to 10,000 cones in a season, eating the fleshy cone scales and releasing 2 million seeds. Long-horned beetles also bore into the cones, helping to dry them and allowing seed dispersal.
Remarkably, one giant sequoia can support more than 150 species of insects, a self-sustaining community where aphids feed on foliage and green lacewings eat aphids; robber flies consume lacewings; flycatchers dine on robber flies; and hawks feast on flycatchers.
None of the more than 80,000 kinds of trees on Earth can be repeatedly struck by 100 million volts of electricity — or a bolt of lightning — and live for another millennia or two, except the sequoia.
Eventually, giant sequoias lose their feet as soil erodes. With gigantic springtime snow loads in their crowns, and high winds and soggy soils, they tumble to their demise.
I encourage everyone — at least once in their lives — to make the pilgrimage to visit these noble trees.