I hiked through a burn scar near Berryessa Lake in Davis, California, in May, almost a year after the Hennessey Fire started there. It was 90 degrees Fahrenheit, the direct sunlight harsh without branches covered in pine needles or leaves to block the sun. The landscape was brown, not unusual for California in the summer, yet punctuated with 10-foot vertical black spokes, the remains of trees. I would have to drive an hour down the winding road from the trailhead before I encountered anything even slightly green on my way out.
I love trees. So when wildfires rip through my home state of California or my favorite travel destinations in the Pacific Northwest or Colorado, I feel the most climate grief.
Wildfire isn’t just sad for nature lovers, but it’s also a huge problem for the planet. Forests are some of our best carbon sequesters, and over the past five years hundreds of thousands of acres in the U.S. have literally gone up in smoke, pouring carbon back into the atmosphere. The only way to directly reverse the effects is to wait for new trees to take the place of the old ones. Given the greater number and intensity of wildfires that have become the norm due to climate change, coupled with insufficient forest management practices, the forests need help to regenerate.
So corporations are stepping up and expanding their tree-planting budgets to address the problem, but tree-planting after a forest fire is different from traditional reforestation projects. It takes a lot of management, care and infrastructure to plant trees. Without tree planting organizations and money, usually from corporate backers, once-forested areas would turn into blank landscapes dotted with shrubs that have out-competed the trees in the wake of fire.
Business involvement in tree planting has a long history. Arbor Day, launched in the 1870s and declared a national holiday a century later, has sparked countless workplace tree-planting events — and the Arbor Day Foundation has involved many corporate partners over the decades. As wildfires have accelerated in recent years, and as companies seek to meet ever-challenging sustainability goals including net zero carbon, corporate tree planting efforts tend to be done in partnership with large nonprofits and at a large scale.
Arbor Day launched the Wildfire Restoration Collaborative in 2020 with corporate partners including Target, Facebook and PepsiCo to help reforest areas that had been burned in the California fires. Another example: American Forests worked with Salesforce to reforest over 1,000 acres burned by the 2018 Camp Fire in California and fires in the Willamette Valley of Oregon after the Whitewater Fire. Intel has worked on the King Fire scare in Sequoia National Forest with the nonprofit.
"From a Salesforce perspective, we’re trying to say, ‘How can we be most effective when we are looking to deploy capital?’" said Max Scher, senior director of sustainability at the software giant. "How should we be thinking about the changing climate in the forests that we’re trying to conserve or restore?"
Right now the answer to both questions sits in reforestation projects post-fire.
According to American Forests’ statistics, 81 percent of reforestation needed on national forest land is wildfire-driven and steadily growing each year. This shift came in the mid-1990s as wildfires increased and timber production slowed, according to Rempel. Previously tree planting dollars were rehabilitating forests that had been clear cut for timber harvests.
"Nowadays, reforestation is becoming synonymous with post-fire restoration," said Austin Rempel, senior manager of reforestation at the nonprofit American Forests. "Planting [projects] are more and more just in fire scars."
Not every fire needs planting
Wildfires are necessary for the healthy lifecycle of a forest and forests have evolved to bounce back, but climate change changes the situation. The first step in any post-wildfire restoration is figuring out if an area will grow back on its own.
"Many scientists, including myself, are worried that these fires are burning differently than they have been historically," said Elizabeth Pansing, forest and restoration scientist for American Forests. "They are burning hotter so we are worried that forest might not necessarily regenerate."
Tree planting efforts have started to focus heavily on preventing forests from being converted to hillsides covered by dirt and shrubs after a fire. The patches that have high severity burns where all the trees have been killed are usually flagged for restoration.
According to Pansing, a fire might sound scary because of the size but the impacts on the ground vary. Even if a fire has raced across a large acreage, a forest retaining a lot of green patches could regenerate on its own.
Nowadays, reforestation is becoming synonymous with post-fire restoration.
Mathew Hurteau, a forest and fire ecology professor at the University of New Mexico, explained that healthy trees will drop their seeds after a fire, so a long narrow burn strip with trees on each side will regenerate. But conifer tree seeds don’t travel far, so if a burn patch is in a perfect circle, that area might need human intervention.
"The [fires] burn so hot that they take out all the vegetation, but they also really cook the soil," Rempel said. "So there's a hard crust that has been cooked to the point where it can’t absorb water and everyone starts to worry about post-fire flooding."
Not the most ideal environment for a new tree to begin life.
Companies want to help but need to stop thinking about individual trees and single fires, according to tree planting experts. Instead, they need to create planting strategies that take into account the entire lifecycle of the tree, the forest, management and future fires.
With fires burning so hot in the past few years, post-fire landscapes are brutal for seedlings. Even if some seedlings naturally take root, they could get washed away by flood or dried out by the constant sun without adult trees to shade them.Even if an organization such as American Forests plants nursery seedlings, a harsh environment remains.
"From the perspective of a seedling, you’ve been growing in a nursery for a year or two and you’ve been coddled," Rempel said. "You’ve had the perfect amount of sun, the perfect amount of moisture, all your needs are met. And then you’re thrown out into a fire scar where there’s no cover, there’s hot wind, and full sun all day."
They are burning hotter so we are worried that forest might not necessarily regenerate.
It’s now standard to use the tree tubes that support seedlings as secondary shade structures to help the seedlings survive and thrive in a burn scar. That’s if a tree-planting organization can find seedlings to begin with, as there is a seedling shortage due to labor, climate change and budget constraints.
Companies need to be in from the start and for the long haul, Pansing added. The best time to plant after a wildfire is a year or two after it has burned. And in fact, it can even be relatively affordable because there is less site preparation necessary if work starts quickly. Shrubs can outcompete seedlings if the landscape is left alone for too long.
"[Shrubs] are coming back faster than anyone’s ever seen," Rempel said. "And so the seedlings we planted, we've actually had to go back once or twice to cut a ring around them just to give them the chance. Because otherwise the shrubs will grow 10 times faster than they can and steal the moisture, and our entire investment will be gone."
Planting for resilience
Reforesting wildfire scars isn’t just about individual seeds replacing the lost trees, it’s also about creating new forests that will be more resilient.
After a fire, Pansing and her team start from scratch to create a better forest. They think about what a forest would look like that is more likely to withstand the next fire. What is the optimal spacing and layout between each tree? How are the pine and leaf droppings that act as fuel for wildfires going to accumulate and be managed? Planting fire resilient species or trees that have been adapted to the changing climate in that region may help, Pansing added.
But this is harder and more complex than the old school, high-density approach to tree planting, which has led to fire-prone landscapes, according to Hurteau.
"We’re not trying to grow a crop," he said. "It’s about using variation across space to create the forest you want to have."
Row planting can be done faster, more cheaply and at a higher quantity, but if companies don't want to see their tree planting investment go up in flames during the next fire, it’s worth changing tack.
Reforestation after fire as carbon offsets
Many tree planting initiatives are completely philanthropic. But as net-zero commitments have exploded in recent years, companies are looking to use tree planting efforts as carbon offsets. Many wildfires happen on national forest land where the sale of offsets has yet to happen, but other obstacles stand in the way of using wildfire restoration as a carbon credit.
Gold Standard, a nonprofit voluntary carbon offset program that verifies tree planting projects, has a rule preventing planting trees for carbon crediting in something that was a forest within the last 20 years for carbon crediting.
"It’s a safeguard against cutting down trees, just to replant them again and again," Owen Hewlett, chief technical officer, said. "But [fire] is a difficult situation because nobody cut the trees down; that was a natural phenomenon." And this challenge points to the underlying issue and importance of permanence around carbon credits. "You can’t compensate [for] emissions with something that’s not permanent," he said.
But with wildfires increasing, it’s becoming more obvious that today's forests aren’t permanent. Instead, the focus is on planting a new and improved forest after a fire.