Scientists agree that trees are an important weapon in the fight against climate change. New forests absorb large amounts of carbon from the atmosphere, but a new study argues people need not plant trees to see a benefit.
Susan Cook-Patton is a forest restoration scientist at the Nature Conservancy who learned an important lesson from her dad. He wanted to grow trees on his land and discovered nature was the best gardener.
“He kept trying to plant oaks, and he was not very successful," she recalls. "Trees weren’t coming up, and so what he has decided to do is just gather buckets of acorns, which he then leaves out on the porch, and then the squirrels get them, and they bury them.”
He found those acorns were more likely to produce saplings. Cook-Patton and her colleagues have studied how forests regenerate without human help.
“If you have seed sources nearby, and the soil conditions aren’t too degraded, just letting the forests come back on their own can cost a whole lot less money, and you’re more likely to get species that are going to be best suited for the conditions in that area.”
She adds that in some places people will need to do the planting or at least take steps to protect young forests.
“Deer are always a big issue, so anything you can do to control deer browse will help.”
And for some lands, it’s important to choose specific kinds of trees.
“You want to focus on getting the right trees for the right place, and if you’re thinking about flood plains you would want species that are good at tolerating flood events.”
The Nature Conservancy scientists have created a map of the United States showing the best places for forest restoration.
In Virginia, for example:
“There are up to 4.4 million acres of opportunity to restore forest cover where they used to be, and if you were able to put trees back on that whole landscape you’d be able to store 14.7 million tons of carbondioxide per year. What does that mean? It’s about the same as removing 3.5 million cars from the roads.”
Most of the lands in question are now serving as pasture, flood plains and open spaces in cities.
