More Than One in Three Tree Species Around the Globe Are at Risk of Disappearing, New Report Finds

Trees are in trouble: More than one-third of known species around the globe are at risk of disappearing, according to a new assessment.

On Monday, the International Union for Conservation of Nature (IUCN) updated its Red List of Threatened Species. As part of that update, the group also published the first Global Tree Assessment, a comprehensive worldwide study involving more than 1,000 tree experts.

Scientists assessed more than 80 percent of known tree species and found that 38 percent were at risk of extinction. In numbers, that means at least 16,425 of the 47,282 tree species studied could soon die out forever.

Trees now make up more than a quarter of all species on the IUCN’s Red List, which includes plants, reptiles, mammals, amphibians and birds.

The group announced the findings during the two-week United Nations Biodiversity Conference (COP16) currently being held in Cali, Colombia.

Trees are “essential to support life on Earth,” says Grethel Aguilar, the IUCN’s director general, in a statement. They remove carbon dioxide from the air, then stash it away in their trunks, leaves, branches, roots and in the soil. They emit oxygen, help prevent soil erosion and play a key role in the water cycle. The forest ecosystems that consist of trees support numerous other organisms, including plants, animals and fungi.

“If we lose the trees, we are losing many other species with them,” says Steven Bachman, a conservation researcher at the Royal Botanic Gardens, Kew, in London, to BBC News’ Helen Briggs. The results of the assessment, he adds, are “shocking.”

In urban areas, trees provide shade and release water vapor into the air, which helps keep neighborhoods cooler. They reduce the need for power-intensive air conditioning, as well as outdoor water use. Trees also provide medicines, food, fuel and shelter to humans.

But despite their wide-ranging value, trees face numerous threats around the world. Some of the biggest are deforestation for agriculture, logging and clearing forests for human development. In warmer areas of the globe, diseases and pests are also taking a toll. Experts aren’t yet sure how climate change will affect trees, but they’re concerned about the impacts of sea-level rise and storms that are becoming more intense and damaging.

Tree species are facing extinction in 192 countries, the new report finds. But their vulnerability varies from place to place. In South America, the continent with the greatest tree diversity in the world, 3,356 out of 13,668 species are at risk of dying out.

Trees that live on islands are also particularly susceptible to extinction, and they made up the highest proportion of at-risk species. That’s because they often grow in small numbers in just a few isolated locations. If those groups disappear, the species is simply wiped out. For example, fewer than 75 mature specimens of the sangre de doncella tree—a red-flowering species that translates to maiden’s blood—remain in existence in Cuba. The IUCN has categorized the tree as “critically endangered.”

To save the world’s trees, experts are calling for more habitat protection and restoration, as well as other conservation efforts like saving seeds in seed banks and growing specimens in botanic gardens.

“Can you imagine a planet without trees?” Aguilar said during a press briefing, as reported by CNN’s Rachel Ramirez. “We, humans, are capable to reverse this and save these trees that we depend on, so the task that we have is huge.”

Three years ago, the leaders of more than 140 countries agreed to try to end deforestation by 2030. Some countries, like Brazil, have been successful at slowing deforestation. However, overall global progress has been lagging—putting the world off track for meeting that goal.

At the conference in Colombia this week, nations are discussing how developing nations rich in biodiversity might afford to protect the plants and wildlife within their borders, writes the New York Times’ Catrin Einhorn. Last year, Brazil proposed a plan that would establish a fund to pay developing countries to preserve forested land.

“There is a huge blind spot in terms of understanding and prioritizing the value of standing forests,” says Erin D. Matson, a senior consultant for Climate Focus, a company working to reduce greenhouse emissions, to the New York Times. “Governments are often affected just as much by profit motive as private companies, and it’s much easier to make money by clearing a forest or harvesting timber from a forest than by protecting and conserving a forest.”

Sarah Kuta | READ MORE

Sarah Kuta is a writer and editor based in Longmont, Colorado. She covers history, science, travel, food and beverage, sustainability, economics and other topics.