Wednesday, 3 March 2010

Biggest Plant in the World a Quaker?



One of the candidates for the biggest living thing in the world is, surprisingly at first, a poplar. Pando (not to be confused with the black and white creature that nibbles bamboo) is the name given to a clonal colony of Quaking Aspen (Populus tremuloides) in the USA.

Locally they also call it the Trembling Giant, in reference to quaking/trembling nature of this obviously extensive poplar plant. It's leaves shake with any waft of wind, or perhaps with excitement about being perhaps the biggest living thing on Earth.

Pando is Latin for 'I spread' which is adpt, and it is certainly big. Genetic tests have shown that this 43 hectare collection of trunks is all connected by one massive root system. The 'plant' in total is estimate to weigh 6,000 tonnes. It's also said by some to be one of the oldest organisms on earth, dating back perhaps 80,000 years - however this is disputed!

This giant organism grows in Utah and was first announced to the world in 1992 and it even has its own stamp, released in 2006, where it was apparently considered to be one of forty 'Wonders of America'.

There is some debate about whether Pando is an interconnected organism and whether if it is, it is the largest. There are reputedly 80 ha Quaking Aspen 'forests' elsewhere in Utah. And some scientists have suggested that parts of this extensive root system are dead so it isn't really one organism.

All this I gleen from Wikipedia, which is fine. Jim Croft alerted me to this posting, but also to another candidate for the oldest, biggest and heaviest living organisms. Fungi often rise to the top of the list.

A honey fungus, Armillaria ostoyae, in an Oregan forest is estimated to cover 890 ha and to be at least 2,400 years old. All you see in the forest, if you are lucky, are the fruiting bodies of the fungus - the toadstools. The bulk of this plant, like the poplar, is underground.

I've mused before on old, or indeed immortal, things and it soon becomes a matter of semantics (or algae, as usual, being the winner!).

As for the biggest, when I last looked into this it seemed that the most massive non-clonal plant on Earth is a 2,000-tonne Giant Sequoia (Sequoiadendron giganteum) in eastern California, nicknamed General Sherman. This single trunked tree is 83 metres tall, and 24 metres in circumference at its base.

Somewhere in Sicily there grows a 4,000-year-old Sweet Chestnut (Castanea sativa), called ‘The Tree of a Hundred Horses’, which had a circumference of 58 metres in 1780 (and has since split into three).

In Australia, there is a 10,000-year-old Huon Pine (Lagarostrobos franklinii) at Mount Read, in Tasmania, with a spread of over 2.5 hectares. This is still well short of the Pando and our fungal friends.

In case you are wondering, the world’s tallest plant is apparently a 113-metre-high Redwood (Sequoia sempervirens) in Humboldt Redwoods National Park, California. Conifers such as the Californian Redwoods regularly reach over 100 m, but not much more (the tallest conifer every recorded was apparently a 126 m Douglas Fir, Pseudotsuga menziesii).

The tallest flowering plant, as distinct from a conifer, is the Mountain Ash (Eucalyptus regnans), found in southern NSW, Victoria and Tasmania. Although there are claims of Mountain Ashes over 120 m tall, the tallest ever accurately measured was 107 m.

Today the tallest living specimen of Mountain Ash is a 97 m tree called ‘Icarus Dream’ in the Styx Valley in Tasmania, but the relatively rapid growth of eucalypts means that others may top 100 m in our lifetime. For those of a more parochial bent, the tallest tree in New South Wales is apparently a Flooded Gum (Eucalyptus grandis), near Bulahdelah on the North Coast.

Image: The treetop walk at Cement Creek, near Warburton in Victoria - bringing you closer to, but still far from, the canopy of the majestic Mountain Ash.

5 comments:

Chris said...

Very good stuff to know. The title struck me because I always figured it was the blue whale. ;-)

Tim Entwisle said...

Thanks Chris. Yes it's all in the semantics really - biggest plant, animal, living thing... And then you have the debate about what constitutes a single 'thing'. A Blue Whale, at least, it pretty clearly defined, although it does connect, genetically, with its offspring and ancestors!

Chris said...

Indeed. I never knew acres of plants interconnected by a root system is considered ONE organism.

On a side note, that probably means these plants just self propagated for hundreds of years. That's amazing!

Jarrett said...

Richard Preston's book The Wild Trees is the story of a group of young tree-climbing naturalists obsessed with measuring redwoods and finding the tallest one. He suggests that this quest is always unfinished, and that in any case, if they did know which tree was the tallest, they (and the National Park Service) wouldn't tell anyone. They probably wouldn't even tell the Park Service.

(A couple of chapters also deal with climbing mountain ashes in Victoria, where Preston tries to sow similar uncertainty.)

In any case, it is almost impossible to perceive the height of redwoods from the ground, as they grow only in dense groves at the bottoms of coastal river valleys, obscuring one another and preventing the viewer from getting far enough back from them to see the whole tree.

So the height statistics come apart from the tree in human experience. The larger redwoods located near highways have large wooden signs explaining their statistics. It's common to see a car-load of tourists take a photograph of themselves gathered around the sign -- a shot that omits the tree entirely.

I used to find this funny, but the more I explore redwoods the more impossible it is to photograph them, or to connect their statistics to the sensations of their presence. So perhaps these tourists are wise.

Tim Entwisle said...

Yes, quite true Jarrett. In fact the granduer of the Mountain Ash forests in Victoria is more about passing through the towering trunks - i.e. more about the forest than an individual tree. You never really see a full tree from top to bottom, and that is part of the experience.