Destructive fires in recent years that burned too hot for forests to quickly regrow have far outpaced the US government's capacity to replant trees.
The Biden administration has said the government will plant more than one billion trees across millions of acres of burned and dead woodlands in the US West, as officials struggle to counter the increasing toll on the nation's forests from wildfires, insects and other manifestations of the climate crisis.
"Our forests, rural communities, agriculture and economy are connected across a shared landscape and their existence is at stake," Agriculture Secretary Tom Vilsack said in a statement on Monday announcing the reforestation plan.
"Only through bold, climate-smart actions ... can we ensure their future."
Destructive fires in recent years that burned too hot for forests to regrow naturally have far outpaced the government's capacity to plant new trees. That has created a backlog of 4.1 million acres in need of replanting, officials said.
The US Agriculture Department said it will have to quadruple the number of tree seedlings produced by nurseries to get through the backlog and meet future needs.
That comes after Congress last year passed bipartisan legislation directing the Forest Service to plant 1.2 billion trees over the next decade and after President Joe Biden in April ordered the agency to make the nation's forests more resilient as the globe gets hotter.
Officials had to pursue a more piecemeal approach with incremental measures such as Monday's announcement since most of the administration's agenda on the climate crisis remains stalled due to disagreements within Congress.
To erase the backlog of decimated forest acreage, the Forest Service plans over the next couple of years to scale up work from about 60,000 acres replanted last year to about 400,000 acres annually, officials said.
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Blazes have charred 5.6 million acres so far in the US this year, putting 2022 on track to match or exceed the record-setting 2015 fire season, when 10.1 million acres burned.
Many forests regenerate naturally after fires, but if the blazes get too intense they can leave behind barren landscapes that linger for decades before trees come back.
The Forest Service this year is spending more than $100 million on reforestation work and is expected to further increase in coming years, to as much as $260 million annually.
To prevent replanted areas from becoming similarly overgrown, practices are changing so reforested stands are less dense with trees and therefore less fire-prone, said Joe Fargione, science director for North America at the Nature Conservancy.
But challenges to the Forest Service's goal remain, from finding enough seeds to hiring enough workers to plant them, Fargione said.
Many seedlings will die before reaching maturity due to drought and insects, both of which can be exacerbated by the climate crisis.
Living trees are a major “sink” for carbon dioxide that’s driving the climate crisis when it enters the atmosphere, Fargione said. That means replacing those that die is important to keep climate change from getting even worse.
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