Towering over the forests of California for thousands of years, the giant sequoia stands as the largest living tree on Earth and one of nature's most awe inspiring creations

High on the misty western slopes of California's Sierra Nevada mountains grows a living creature so immense and so ancient that it seems to belong to another age entirely. It is the giant sequoia, a tree of such staggering proportions that standing quietly beneath one can leave even the most seasoned traveller feeling wonderfully small and deeply humbled.

Giants that touch the sky

The giant sequoia is widely celebrated as the largest living tree on the entire planet, a remarkable title it earns not through its height alone but through its truly colossal overall bulk. While a few other trees may grow slightly taller, none of them can rival the sheer volume of solid wood contained within the massive trunk of a fully grown sequoia.

The most famous of them all is a single tree affectionately known as General Sherman, which rises to a breathtaking height of around two hundred and seventy five feet above the forest floor. Its enormous trunk measures more than one hundred feet around at the base, making it by volume the biggest single stem tree that has ever been reliably measured anywhere on Earth.

Older than empires

Beyond their astonishing size, what makes these trees so deeply remarkable is their almost unimaginable longevity across the very long march of time. A giant sequoia can live for well over three thousand years, meaning that some of the oldest individuals alive today were already standing tall long before many of history's greatest empires had even begun to rise.

The great General Sherman itself is estimated to be somewhere between two thousand two hundred and two thousand seven hundred years old, and the very oldest known sequoias may well be older still. To walk among these trees is therefore to walk among living witnesses to thousands of years of quiet, patient and largely unseen natural history.

A tree built like a fortress

Part of the secret behind the sequoia's incredible endurance lies hidden within its thick and remarkably protective outer bark. This soft, spongy, reddish brown covering can grow to be more than a foot in thickness, wrapping the entire trunk in a kind of natural armour that shields the living tree from intense heat, from hungry insects, and from slow decay.

This extraordinary bark also contains very little of the flammable resin that is found in so many other kinds of trees, which allows a mature sequoia to survive fires that would easily destroy its neighbours. Combined with sturdy branches that begin high above the ground, this natural defence has helped these gentle giants weather countless seasons of drought, storm and flame.

Born from fire

Perhaps the most surprising fact of all is that the giant sequoia does not merely tolerate fire but actually depends entirely upon it in order to bring fresh new life into the surrounding forest. The intense heat of a passing blaze helps to dry out and gently open the tree's tightly sealed cones, releasing a fine shower of tiny seeds down onto the waiting ground far below.

At the very same time, the crackling flames clear away the tangled undergrowth and competing plants that would otherwise crowd out any fragile young seedlings. This leaves behind bare, mineral rich soil and bright sunny openings in the forest canopy, creating exactly the conditions that a tender young sequoia quietly needs in order to take root and one day grow into a giant of its own.

A home found in only one place

For all of their great fame and grandeur, wild giant sequoias grow naturally in only one small corner of the entire world, clinging to the western slopes of the Sierra Nevada mountains in California. Here they are scattered across roughly ninety separate groves, each one a precious island of these ancient trees standing within the wider mountain forest.

This remarkably limited natural range means that every single grove carries an enormous importance for the future survival of the species as a whole. The trees depend closely on the particular climate of these high mountain slopes, where the deep winter snows slowly melt to provide the steady supply of moisture that their thirsty roots quietly require throughout the year.

Guardians facing a new danger

Although these mighty trees have stood firm against fire for many thousands of years, they are now confronting a serious threat unlike anything else in their long and eventful past. In recent times, a series of unusually fierce and destructive wildfires has swept through their mountain groves, burning far hotter and higher than the gentle natural fires the sequoias evolved alongside.

Alarmingly, more than seventeen percent of all the world's mature giant sequoias have already been lost to these extreme fires in just the last decade or so. Dedicated teams of forest guardians now work tirelessly to protect the surviving trees, even wrapping the base of the most famous giants in protective shielding, so that these ancient wonders may continue to inspire the generations still to come.