Mar 20, 2020
Every year, the planet loses an average of 26 million hectares of forest cover—that’s the size of the United Kingdom.
Every hectare lost means fewer trees to keep our water and air clean, to mitigate the effects of climate change through carbon storage, and to provide food, medicine, and fuel for more than a billion people worldwide. The list could go on and on.
It’s more urgent than ever to raise awareness of the importance of forests. That’s why today we celebrate International Day of Forests, as we have done every year since 2012.
Because this year’s theme is forests and biodiversity, I’d like to share some facts that highlight the impressive diversity of trees. I hope it will not only pique your curiosity about trees, but also inspire you to become more engaged in this critical conservation.
It was only in 2017 that we were finally able to accurately estimate the number of tree species in the world: more than 60,000! Botanical Gardens Conservation International, an advocacy group, compiled the list by using data gathered from its network of 500 member organizations. They found that Brazil, Colombia, and Indonesia have the most tree species—home to at least 5,000 species apiece. Another finding was that more than half of tree species are unique to a given country, suggesting that they are vulnerable to potential threats, such as deforestation from extreme weather events or human activity. Most importantly, about 300 species have been identified as critically endangered, that is, with fewer than 50 trees remaining in the wild.
Trees are some of the largest and oldest living things on the planet. The biggest tree is a giant sequoia in California’s Redwood Forest. It is as tall as a 30-story building! California holds the record for the oldest living trees, too. Some of the state’s bristlecone pines and giant sequoias are thought to be between 4,000 and 5,000 years old.
When I was a kid, I used to wonder how trees grew so large without eating, until I learned about photosynthesis. That’s the process by which plants absorb sunlight for sustenance. But interestingly, not all trees photosynthesize. There are about 3,000 plant species that produce no chlorophyll, considered the essential ingredient for photosynthesis. For example, an “albino” redwood survives by consuming sugar through its roots and those of neighboring redwood trees, giving its leaves a curious white hue instead of the normal green.
Trees are master adapters, and this has allowed them to thrive in almost all types of ecosystems:
- While saltwater can kill trees, mangrove trees thrive in coastal areas. They are nature’s desalination plants, with roots that can filter out around 99% of the salt contained in seawater.
- Drought-tolerant trees have longer roots than trees located in wetter climates, covering an area up to twice the diameter of the canopy. For example, Velvet Mesquiet roots can grow underground to depths of up to 53 meters to access deep ground water!
- Juniper trees are incredibly resilient in high-altitude settings, thanks to their tiny leaves and waxy coating that keeps moisture in. Junipers can survive in altitudes as high as 4,900 meters, making them one of the highest-altitude trees on earth.
I’ve always been interested in trees. There is something called the biophilia hypothesis, which links fascination with trees to the human tendency to seek connections with nature and other forms of life. I definitely identify with this. I think we have so much to learn from trees: they are self-sufficient, serene, strong, constantly growing to reach new heights for sunlight, and deeply rooted in their community.
On this International Day of Forests, I ask you to take some time to reflect on your relationship with nature, and with trees in particular. I think you will find the exercise both inspiring and relaxing!
