Planting trees has been touted by some scientists as one of the best ways to combat climate change. While it's not a panacea, planting trees is good for everything from providing habitat to mitigating air quality to capturing and storing carbon emissions.
A growing body of research is showing that trees can positively impact both the climate and human health. As the power of trees becomes more evident, many people are looking to get involved in planting them. Just last month, Ethiopia planted over 350 million trees in one day, smashing previous records.
But tree planting isn't as easy as just burying some acorns in the ground—where, what, and how you plant matters. Here's everything you need to know about planting a tree.
Why should I plant trees?
About a quarter of human emissions come from land-use like agriculture, which clears forests. The good news is that planting more trees can both slow climate change and increase our capacity to adapt to it, a recent report from the United Nations noted.
As more people move to cities, places that used to be rural towns or farmland open up, affording opportunities for more forests to grow; planting trees in areas formerly converted to other land uses is called "reforestation."
Some of the most important target areas for reforestation are those that have been heavily deforested or damaged by disaster. Climate change is ramping up extreme weather events, such as fires and floods, which can wipe out huge swaths of tree cover. Pests and pathogens, too, move around as weather patterns shift, and can decimate species that haven’t developed immunity.
The combined effects of this kind of large scale destruction harm ecosystems and throw the carbon cycle further off balance, releasing stored carbon into the atmosphere and contributing to the greenhouse effect. Planting new trees can help offset these losses, too.
On a smaller scale, tree planting can provide habitat for other species and cool concrete-covered cities (pavement makes cities hotter), as well as provide shade or wind-breaks to your home. The task of reforestation may seem daunting, but we’ve got some tips to help.
Getting started: Where to plant
A good place to start planting is your own backyard, where trees and shrubbery can benefit you as well as the planet.
The exact location of your new trees will come down to what you want from them. Planting trees to the north and northwest of your house can provide a windbreak, while planting them to the west can help provide shade, according to the Arbor Day Foundation. Both of these undertakings can reduce your heating and cooling costs.
There are other energy-saving strategies involving greenery to look to as well, including planting a shrub to shade your air conditioning, which cools it and makes it run more efficiently. Just make sure to avoid planting trees under or near utility lines, as that can cause service interruptions or safety hazards.
All this tree talk may inspire you to start planting wherever there’s open space. However, because private property is a thing under capitalism for now, you can’t just plant trees anywhere you feel like. While the planet may appreciate five extra trees in the driveway next door, your neighbor may not.
It’s not just private land that’s off-limits to enterprising tree planters, either. Just because land is publicly owned doesn’t mean that you can plant whatever you want on it. Public land is managed by the city, state, or federal governments, and they’re in charge of reforesting.
The good news is that a lot of these organizations accept volunteers or donations. The Forest Service, for example, has a long-running Plant-a-Tree Program, in which donations go directly to reforestation efforts. You can also call your local parks department and volunteer directly, planting on public land. You could also take on the notoriously grueling (but worth it) Canadian summer job of tree planter in some seriously stunning locales. One summer tree-planter, Sydney Jones, said that she still thinks about the thousands of trees she planted over four seasons in Canada.
"I think of all the ecosystems that have formed around the trees I planted: the bird that will land on the branch, the worms in the soil," Jones said. "Those trees will survive for years and years, long after I’ve died."
Picking the right tree species
The first question to ask when planting a tree is: will it survive? Some trees can withstand the cold snaps of a New England winter, for example, and others are more suited to the dry conditions of a Southwest desert.
The Arbor Day Foundation offers a service called Tree Wizard that recommends trees based on your zip code and preferences. At the end of your search, you can buy the seedlings. The Forest Service’s similar service, i-Tree Species, allows you to input the ecosystem services you want (such as carbon storage or heat reduction).
The Crowther Lab at ETH Zurich (which produced a viral study this year arguing that planting billions of trees is the most effective climate change solution) also has created an interactive map that recommends specific species to plant.
After that, it’s important to ensure that the tree will do more good than harm. Planting a tree that’s native to an area can help to provide habitat for other native species. However, planting an invasive species of a non-native tree can result in the trees outcompeting native species for available resources. Many species also carry pests or pathogens that can be fatal to native trees.
However, there’s a distinction between non-native and invasive. Indeed, changing climate conditions can sometimes mean a tree once common in an area will now struggle. “If a tree species comes into an area introduced by a human, it’s non-native,” Arbor Day Foundation vice president Woodrow Nelson said. “It’s not considered invasive unless a non-native species is displacing one or more of the native organisms.”
When in doubt, consult your local parks department for advice on what trees are right to plant.
How to plant a tree, step-by-step
Now that you’ve picked out your tree and your spot, it's time to actually plant the tree.
Planting tree seeds Johnny Appleseed-style is unlikely to get you anywhere, as many won’t even sprout. Instead, you want to purchase seedlings, young trees that are already old enough to be stable after planting. Where you plant them is going to depend on their individual needs in addition to their intended function for your home—large trees need to be planted farther apart, for example.
The best time to plant is during the dormant season (after the leaves fall in autumn, or before spring flowers start blooming) according to the International Society of Arboriculture. Here’s how to do it:
- Before you start planting, you should locate all your underground utilities by asking your utilities provider.
- Dig a hole that is no deeper than the root ball, but twice as wide. Don't plant the tree just yet, as the next step is important.
- To test the drainage, fill the hole with water. If it doesn’t drain within 24 hours, pick another site—you don’t want your trees’ roots underwater.
- Orient your tree correctly. Let the trunk flare (the part of the trunk that spreads outwards to the roots) sit just above ground, so as not to suffocate the tree. Handling by the root ball (not the trunk), place the tree in the ground and make sure it’s centered and straight.
- Fill the hole with dirt, without packing it down too firmly.
- Pruning, or removing dead branches, should only be done if really necessary. Staking, too, isn’t required for all trees, and you should consult with a professional before you stake yours.
According to Nelson, the most common problem is that people plant their trees too deep into the ground and they struggle. The first year of growth is also critical, and Texas A&M Forest Service advises watering slowly and thoroughly with a hose.
“If you’re going to plant a seedling tree, plan to water it every week that first year,” Nelson said. “You can’t just plant it in a field and expect them to do really well.”
Support tree-planting organizations
If you want to move beyond your community and get involved with large-scale reforestation, supporting tree-planting campaigns is a great place to start.
Organizations like the National Forest Foundation plant millions of trees, and accept donations that go directly to tree planting efforts. The Nature Conservancy has a campaign to plant a billion trees in countries worldwide.
The Crowther Lab created another interactive map, this one highlighting reforestation projects around the world. Supporting the organizations behind such projects, either with time or donations, can help to restore natural ecosystems. The Crowther Lab also provides resources to invest responsibly, ensuring that your money supports ecosystem growth, not fossil fuels.
Planting billions of trees may not stop climate change, but it’s a good start. Whether you have room in your lawn or a few dollars to spare, you can participate in a worldwide effort to make the planet greener.
“There’s always room for one more tree,” Nelson said.