Trillion Trees Sounds Great. Now. Anybody Got some Trees?

I have no problem with proposals to plant a trillion trees, sounds like a great idea, notwithstanding questions about exactly where you’re going to find space for that, which would require an area equal to three Indias.

If we had some ham, we could have ham and eggs, if we had some eggs.

Eureka Alert:

The REPLANT Act provides money for the US Forest Service to plant more than a billion trees in the next nine years. The World Economic Forum aims to help plant a trillion trees around the world by 2030. Many US cities have plans to shade their streets with millions of trees. Major government and private funding is being invested in planting trees as a powerful tool to fight climate change, protect water, clean air, and cool cities. In short, trees are hot.

But new research shows a troubling bottleneck that could threaten these efforts: U.S. tree nurseries don’t grow close to enough trees—nor have the species diversity needed—to meet ambitious plans.

The study was published in the journal Bioscience on July 31, 2023.

“Trees are this amazing natural solution to a lot of our challenges, including climate change. We urgently need to plant many millions of them,” says University of Vermont scientist Tony D’Amato who co-led the new research. “But what this paper points out is that we are woefully underserved by any kind of regional or national scale inventory of seedlings to get the job done.”

A team of 13 scientists, led by D’Amato and UVM post-doctoral scientist Peter Clark, studied 605 plant nurseries across twenty northern states. Only 56 of these grow and sell seedlings in the volumes needed for conservation and reforestation and only 14 of them were government-operated, they report. The team was more dismayed to discover an “overwhelming scarcity of seedlings,” they write, from different species and “seed collection zones”—trees adapted to local conditions and climate. In essence, forest nurseries tended to maintain a limited inventory of a select few species, electing to prioritize those valued for commercial timber production over species required for conservation, ecological restoration, or climate adaptation. Moreover, many areas had no locally adapted tree stock available. (See map for example.) And within the seedlings available, there were not enough types of trees and “future-climate-suitable” genetics to meet goals for conservation and forest restoration in a hot future.

“The world is thinking about a warming climate—can we plant towards that warming climate? We know we’re losing ecologically important species across North America and around the world. So, the goal is: can we restore these trees or replace them with similar species? It’s a powerful idea,” says UVM’s Peter Clark, the lead author on the new study. “But—despite the excitement and novelty of that idea in many policy and philanthropy circles—when push comes to shove, it’s very challenging on the ground to actually find either the species or the seed sources needed.”

“The number of seedlings is a challenge,” Clark says, “but finding the diversity we need to restore ecologically complex forests—not just a few industrial workhorse species commonly used for commercial timber operations, like white pine—is an even bigger bottleneck.”

One extreme example is red spruce. This ecologically important species along hundreds of miles of eastern North America has been under stress for decades from climate change, pests, and land clearing. Yet, in their 20-state survey, the team only found two tree nurseries that had inventory of red spruce, a species from which many millions of seedlings are needed to meet restoration goals. “Remarkably, only 800 red spruce seedlings were commercially available for purchase in 2022,” the team reports in their new Biosciencestudy, “—enough to reforest less than one hectare.”
 

“It really points to just how bare the cupboard is when it comes to the diversity of options,” says Tony D’Amato, director of the Forestry Program in UVM’s Rubenstein School of Environment and Natural Resources, “but also the quantity that’s needed to make any meaningful impact.”

Inside Climate News:

A 2019 Swiss study, for example, estimated that globally, there was the potential to protect and regrow trees on about 3.5 million square miles of land (an area a little smaller than the United States). Doing so, the study projected, would increase the global forest cover by 25 percent and capture and store about a quarter of the carbon in the atmosphere when the forests matured.

Those figures are disputed, but the research has increased interest in the trillion trees idea, and the study is one of the supporting documents for the Trillion Trees Act in Congress.

Separate from the U.S. political process, the international Trillion Trees initiative promoted by the conservation coalition wants to protect and regrow one trillion trees around the world by 2050. The main focus is to protect key forests like the Amazon, and to support natural regrowth in logged areas.

Additionally, the 1T.org platform, launched after the Davos conference, with major partners like Salesforce, Microsoft and Deloit, is aiming to accelerate forest restoration and conservation by finding financing, for example, with app-based crowdfunding. That could help pay for high-tech tools like satellite data and artificial intelligence to guide precision forestry and to monitor tree and soil carbon storage.
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Climate scientists and many Democrats on the House committee greeted the proposed tree planting legislation skeptically, saying that the only real climate solution is to cut greenhouse gas emissions to zero as soon as possible. 

Forests can only be part of a long-term plan to curb global warming after that happens, Yale evolutionary biologist and ecologist Carla Staver testified at the Trillion Trees Act hearing.

“Our primary focus must be reducing our dependence on fossil fuels,” she said, adding that any plausible attempt to limit global warming within our lifespan must also include forest protection and reforestation. “However, it is also crystal clear that tree planting alone will not fix our ongoing climate emergency,” she said.

In February, a coalition of 95 environmental groups sent a letter to Congress opposing the Trillion Trees Act as the “worst kind of greenwashing and a complete distraction from urgently needed reductions in fossil fuel pollution.”

As written now, the proposed law would count biofuel from forests as carbon neutral, a claim that’s contested by climate advocates and scientists, who have said the push to burn wood for fuel actually threatens global climate goals. It would also limit public and judicial reviews of forest management and even create incentives for more logging of existing old-growth forests, which are the best existing carbon sinks, said Alexander Rudee, a forest policy analyst with the World Resources Institute.

“Requiring harvests to increase annually will likely cause a net loss of trees, at least in the short-term, since natural regeneration isn’t 100 percent effective, and could increase emissions from burning or decomposing harvest residues,” Rudee said.

Magical Thinking

One reason the trillion-tree meme caught on may be that the world wants a simple solution to climate change and is ready for a positive message. Everyone can picture the act of placing a seedling in the ground and helping it grow, a nurturing symbol that must be part of our earliest collective memories as a species.

But Colorado State University atmospheric scientist Scott Denning, who studies how carbon moves through the global climate system, said the basic numbers of the trillion trees story don’t add up.

“No doubt, if you replaced every area of non-forest with forest, you could sequester a lot of carbon,” Denning said. “But very little of the world is available for planting a trillion trees. Most of the land that might be suitable is in use for farms and cities. Most of the places that can support forests, like the Amazon, Congo, Indonesia and Southeast Asia, already have forests.” 

He added, “You have to fix global warming by stopping burning oil and gas. To think you can just plant trees and keep burning oil and gas doesn’t make sense. We have to to get away from magical thinking.”

And while trees might help the planet survive in the long run, scientists say, first we have to save them. Global warming is a threat-multiplier for drought, fires and pests that have killed trees across millions of acres in the last 20 years. And forests all over the world are already in the full grip of the climate crisis, said University of Arizona ecohydrologist David Breshears. 

The forests around Breshears’ lab in Tuscon, near the shrinking southern end of the western North American forest belt, have been one of the mortality hotspots for trees. Planting a trillion trees around the world wouldn’t change that, he said.

“We’d like more trees to slow down the warming. But the warming we’re trying to slow is killing the trees. There’s real concern that we’re going to be losing a lot of trees, with more frequent die-offs.

“We need to hold on to the trees that we have,” Breshears said.

University of Montana scientist Diana Six says that widespread tree planting, like everything else we do with nature, requires caution.

“People think, what could be bad about planting more trees, but few have the background to understand the ecological issues,” she said, adding that any major tree-planting program needs to look closely at many related factors, including water and potential social impacts like the dislocation of communities.

“People think they’re going to put these trees in and they’ll grow and live happily ever after,” Six said. “A lot of places that don’t have trees are just too dry—you can’t just stick them in the ground and poof, have a new forest. And they don’t think about the time frame of trees.

“These trees are going to have to grow well and live a long time and not be prone to disease and insects, to capture a lot of carbon,” she said. “This is a multigenerational commitment to take care of these forests. They can’t be harvested, and you can’t just plant them and walk off.”

Washington Post:

The researchers also highlighted that planting a trillion trees would require an enormous amount of land — 900 million hectares, or nearly three times the size of India. It would be nearly impossible to acquire that much land without disturbing grasslands or farmland, whichalready store carbon. Although producing renewable energy is also land-intensive, avoiding the same amount of carbon emissions by building more wind and solar farms would require only 15 million hectares by 2050, the authors found.