May 2020 − Inspiring Science
There are approximately 65,000 known tree species worldwide, and some of them have made quite a name for themselves. They are higher, older or heavier than their peers – and they continue to amaze researchers and nature-lovers alike.
© iStockBiblical Age
969 years old – according to the Old Testament, this was the age reached by Methuselah. It is therefore not surprising that the oldest living tree in the world known today has been named after him: Methuselah, a specimen of the bristlecone pine, has been estimated to have thrived and survived in the White Mountains of California for approximately 4,850 years. The White Mountains, as well as Nevada and Utah, are home to the ancient tree species, many of which are several thousand years old. The secret behind their longevity: in contrast to the DNA of, for example, humans, which is subject to pre-programmed, natural deterioration, this particular pine has an extraordinary capacity for repairing and reproducing damaged cell material. Moreover, the tree has adapted: pests hardly ever infest its robust wood; the dry surrounding air protects it from rot, and the vast distances between individual trees prevent extensive fires.
Not only one, but two records are held by the Seychelles palm tree, also known as the Seychelles nut: in addition to the largest
flower and a cotyledon that measures four meters, this tree develops the largest and heaviest seeds in the plant world. The giant seeds weigh up to 18 kilograms, and up to three can be found inside a single ripe fruit. The ripening process, however, takes time: only after six to seven years does the fruit fall from the tree, and it takes another two years to germinate – maybe. The complicated reproductive behavior of the tree is the reason why its existence is limited to the Seychelles. The name of the fruit, “Coco de Mer”, meaning “nut of the sea”, originates from a misunderstanding; for the longest time, people believed that the seeds drifted across the ocean to spread the species; in fact, they simply sink. Today, this palm tree is listed as an endangered species.
The trembling poplar, whose white trunks protrude from the Utah earth, holds a record that may not be immediately obvious: behind the modest surface, there exists what could possibly be the heaviest living being on earth. The network of roots of its 40,000 trunks is connected underground and thus forms a single organism that spans 43 hectares and would weigh six million kilograms. It is aptly named “Pando”, from the Latin for “to expand”. Ironically, wildfires have presumably enabled the vast expansion of the tree: fires destroyed the trunks, but never the root network, which subsequently sprouted anew on the surface. Without this survival mechanism, other trees, mainly conifers, would have competed with the tree, which is sensitive to the dark, for space and resources. Life as a poplar grove, however, is not entirely without danger: fire suppression by humans, as well as grazing of young trees by deer and cattle, have increasingly afflicted the record holder in recent years.
Like Father, like Son
Hard to ignite, resistant to pests and easy to work with: the coastal redwood, also known as Sequoia sempervirens, delivers perfect timber, which is why it has seen massive clearcuts since the 1850s. Today, you will find a mere ten percent of the original population in California’s national parks. Two particularly magnificent specimens live in Redwood National Park, the name of which may be traced back to the striking red wood of the giant Sequoia. Helios and Hyperion, named after the Greek sun god and his father, are considered the tallest trees on our planet. The slightly taller Hyperion measures an impressive 116 meters. How he manages to transport vital fluids to the top, against the force of gravity, remains a topic of debate among scientists. Most likely, though, this feat comes very close to the limits of what is biologically possible.