This story appeared in the May 2020 issue and was published online on April 17, 2020. Subscribe to Find out magazine for more stories like this. The article has since been updated.
Powerful facts about trees you never knew
1. I think I will never see an organism so alive as a tree. Without these woody, perennial members of the plant kingdom, we might still be rolling around on the sea floor.
2. About 400 million years ago, early trees transformed Earth’s environment by reducing atmospheric carbon. The result: more hospitable ecosystems for marine animals experimenting with life on land.
3. Researchers described one such attractive habitat in December 2019 Current Biology: The find, the earliest forest in the fossil record, is approximately 385 million years old. The site included primitive, fern-like cladoxylopsids as well as species thought to have evolved millions of years later.
4. Some of these more advanced varieties also had extensive root systems spreading more than 30 feet across, suggesting that the trees became larger earlier than previously documented.
5. Today’s biggest of the big ones are the tall redwoods of California; the highest is about 380 feet. But don’t sell The Australian Eucalyptus regnans short. Also known as mountain ash, one specimen in 1881 measured 374 feet.
6. A calculation made by a professional surveyor is considered reliable – although they cut down the tree to check it.
7. The tallest living ash tree found in Tasmania is about 330 feet tall. A forest fire in 2019 damaged the mighty tree known as the Centurion, but it survived. More than a dozen other giants on the Australian island were not so lucky.
Read more: We have lost 35 percent of our forests in the last 300 years
8. Climate change is fueling extreme fires, threatening trees of all sizes. At the same time, trees are key assets in the fight to save the planet. America’s forests, for example, offset up to 20 percent of our annual carbon emissions, according to the US Forest Service.
9. So are more trees the answer to the current crisis? Perhaps. In July, a study in Science announced “global tree restoration as our most effective solution to climate change yet.”
10. The authors identified an additional 2.2 billion acres of land worldwide—an area the size of the entire United States, including Alaska—that could be converted to forest without disturbing current urban or agricultural land.
11. However, other researchers have raised concerns about haphazard tree planting. For example, depending on the locality, adding more trees can increase fire risk, stretch already limited water supplies, and disrupt established ecosystems.
12. Furthermore, most current reforestation projects focus on establishing tree plantations or mixing crops with trees, rather than allowing the forest to regenerate naturally. Per acre, natural forests store six times more carbon than agroforestry areas and 40 times more than plantations.
13. Trees are important to the future of the planet, but they are also great historians. Even slight fluctuations in temperature, precipitation and other factors change the size and density of cells in tree rings as they form, allowing researchers to reconstruct ancient climate patterns.
14. Otherworldly phenomena can also leave a mark. In October, researchers reported a significant increase in radiocarbon dating in growth rings dating to 660 BC in southeastern Poland.
15. The peak in the radioactive isotope may reflect a spike in the number of cosmic rays bombarding Earth when the rings formed. While physicists are still debating the source of these high-energy particles, they may be remnants of violent cosmic events, such as supernovae.
16. Trees can also record Earth’s turbulent internal processes. For example, the Pacific Northwest has long been considered an area of low to moderate earthquake risk. In the 1980s, however, researchers studying the “ghost forests” along its coast came to a disturbing realization.
17. These dead, upright tree trunks clustered in intertidal zones were similar to ghost forests in Alaska that were created when a powerful earthquake caused coastal areas to sink several feet and flood with tree-killing salt water.
18. Among other powerful tree facts, an analysis of the ghost forests of Washington and Oregon revealed the true danger of Cascadia Subduction Zone (CSZ), a fault that extends from Canada’s Vancouver Island to the coast of Northern California.
19. Dating the dead trees helped the researchers discover that the CSZ produces megathrust earthquakes—the most powerful kind—every 400 to 600 years. (It’s been 320 years since the last one was big enough to send a tsunami into Japan.)
20. Haunted forests aside, many mythologies mention the “Tree of Life”. The concept also thrives in modern science. Biologists use cladistics—a method that organizes species on schematic trees—to understand how life has diversified over time. That’s right: trees made us possible, and now they help us trace how we happened.
Read more: What makes a tree a tree?