If we continue down this path, “cities will become warmer, more polluted, and generally more unhealthy for residents,” said David Novak, senior scientist with the US Forest Service and co-author of the study.
Novak says there are many reasons why our trees are shrinking, including hurricanes, tornadoes, fires, insects and disease. But the only reason people can control the loss of trees is intelligent development.
“We see how the tree cover is being replaced by an impervious cover, which means that when we look at the photos, what was has now been replaced by a parking lot or a building,” Novak said.
More than 80% of the US population lives in urban areas, and most Americans live in forested areas along the east and west coasts, Novak said.
“Every time we build a road, build a building, chop down a tree, or add a new one, it affects not only that area, but the entire region.”
The study assessed tree loss based on the role of trees in removing air pollution and conserving energy.
Lost value was $96 million a year.
Novak lists 10 benefits of trees society:
Air Pollution Reduction: Trees absorb carbon and remove pollutants from the atmosphere.
Reduced Energy Emissions: Trees reduce energy costs by $4 billion a year, according to Novak’s research. “Shading these trees on buildings lowers your air conditioning costs. Remove these trees; now your buildings are getting hotter, you’re using air conditioners more, and you’re burning more fuel in power plants, so pollution and emissions are rising.”
Water quality improvement: Trees act as water filters, taking in dirty surface water and absorbing nitrogen and phosphorus into the soil.
Flooding Reduction: Trees reduce flooding by absorbing water and reducing runoff to streams.
UV Protection: Trees absorb 96% of UV radiation, Novak says.
Wildlife Habitat: Birds rely on trees for shelter, food, and nesting. Throughout the world, forests provide a huge variety of wildlife.
Nowak says there are downsides to trees, like being allergic to pollen or big falling branches during a storm, “and people don’t like raking leaves.” But, he says, there are ways cities and counties can manage trees to help communities thrive. “You can’t just say, ‘We won’t have forests.’ We might as well manage trees and work with them.”
“You don’t need a tree in the middle of a baseball field. It is very difficult to do sports if you have trees on the way. Or trees in the middle of freeways.”
Nowak says we can design and manage tree canopies in our cities to help “affect the air, influence the water, influence our well-being.”
Urban forests especially need our help to replace fallen trees. Unlike rural areas, it is very difficult for trees to repopulate in an urban environment with so many sidewalks and asphalt.
“A lot of our native trees can’t really find a place to drop an acorn so they can recover,” explains Greg Levin, co-executive director of Trees Atlanta.
“That’s why the community has to go and actually plant a tree, because the neighborhoods are no longer natural.”
The work is not completed when the seedlings take root. Organizations like Trees Atlanta and their volunteers plan to take care of these young trees for most of their year until they are old enough to thrive on their own.
“We have been trying to prune the trees for 10 years so that they get a good healthy structure.” Levin adds. “We also add mulch around trees to help keep moisture in the ground so the tree doesn’t dry out. We need a lot of patience to plant trees around the sidewalk to make sure they can do the job.”
How you can help stop tree loss
Protect what you have: Novak says the first step is to take care of the trees on your own property. “We think we are paying for our house, and therefore we must maintain it. But since we don’t pay for nature, we don’t need it. And that’s not always the case.”
Trim dead branches from your trees: If they are small enough, do it yourself or hire a company. The risk of limbs damaging your home is greatly reduced with tree care, Novak says.
Notice where your trees might be in trouble: Often you can observe when something is wrong, such as when branches lose their leaves and break, or when mushrooms grow at the base or on trees. You can also hire an arborist or tree expert to assess the condition of your trees annually. Or you can contact your local agricultural extension office for advice.
Don’t remove old trees unless it’s necessary: Instead, try taking smaller actions like deleting branches. “These big trees take a long time to get big: 50 to 100 years. And once they get established, they can live for a long time. guarantees that small trees will grow and it will take a very long time to grow.”
Allow trees to grow in your area: While the aesthetics are different for everyone, this is a cheap way to get cooler yards and lower energy bills. It is also an inexpensive approach to flood and noise control.
Novak says he laughs when his neighbors wonder why there aren’t many trees on their property because “I can hear people starting their lawnmowers.” Fallen seeds need a chance to take root, and constant mowing prevents this. If you don’t like where a seedling grows, you can dig it up and plant it or a new tree wherever you like.
Learn more about trees and get involved: Many cities have tree laws designed to protect very old and important trees. You can get involved by attending city council meetings. You can also help your city plant trees by joining local non-profit groups.
Volunteer or donate to tree planting and research organizations:
Christopher Dawson of CNN contributed to this story.