How Tree Planting Affects the Environment

In September 2020, the UK government pledged to protect and support the recovery of nature across 30 per cent of the nation. It was part of a global pledge across 65 nations to reverse loss in biodiversity, ecosystems and forests by 2030. Campaigners have long called for the UK to increase tree planting to protect the environment. This was their big moment.¹

‌But how does tree planting affect the environment? 

Is tree planting good for the environment?

Trees help the environment in several ways. Forests store and soak up large quantities of carbon dioxide from the air, which is necessary to stop the Earth from heating up. CO2 is a greenhouse gas that traps heat in the atmosphere and raises temperatures. Trees help to keep temperatures stable and cool. Worldwide, forests absorbed over 15 billion metric tons of CO2 each year between 2001 and 2019.²

Trees also provide nutrition to the surrounding soil by feeding it nitrogen and organic material that they shed. This keeps the soil healthy and absorbs more carbon into the soil. A tree’s roots also hold on to water and the soil, which helps to prevent flooding.³‌

Why is planting trees bad for the environment?

Planting trees may not always have the intended effect on the environment if done incorrectly. For one, if non-native species of trees are planted, they can have an adverse impact on local biodiversity, for example, insects that feed on them or other trees. Not all trees are suited to local weather conditions either, and they may die quickly if they cannot adapt to the environment.⁴

Moreover, since forests are dark, they absorb more sunlight in comparison to grasslands or snow. That means that forests can trap more of the sun’s heat and only help the environment in certain places, such as tropical regions, according to some scientists.⁵

Trees are also known to release methane and other chemicals into the air. This is why scientists say that tree planting should be carried out with the intention to help the environment, rather than being pursued without careful planning.⁶

What trees are best to plant for the environment?

Trees are vital for the health of our environment and Earth. They keep our air clean, and they feed the soil. But not all trees are the same. If we want to plant trees to protect the environment, this should be carefully planned.⁷

For one, trees should be native to the region where they are planted. “While ecosystems that existed before areas were deforested may have been highly diverse, reforesting them with only a single type of species (known as monocultures), might result in ecosystems that won’t function as efficiently as they did before”, NASA researchers indicated.⁸

It may also be better to plant trees that absorb more carbon to sequester more carbon from the atmosphere. Researchers are using computer models to better understand how different species of trees and forests interact with the environment.⁹ It would also be better to plant trees with a smaller methane footprint, some scientists say.¹⁰

Either way, the science is clear. Planting new trees boosts local biodiversity and brings more rainfall to the region.¹¹ Let’s plant more trees!

1. Boris Johnson promises to protect 30% of UK’s land by 2030. (2020). BBC News. [online] 28 Sep. Available at: https://www.bbc.co.uk/news/uk-54320030.
2. Streiff, L. (2021). NASA Satellites Help Quantify Forests’ Impacts on Global Carbon Budget. [online] NASA. Available at: https://climate.nasa.gov/news/3063/nasa-satellites-help-quantify-forests-impacts-on-global-carbon-budget/.
3. Worldagroforestry.org. (2021). 5.2 How trees improve soils. [online] Available at: http://apps.worldagroforestry.org/Units/Library/Books/Book%2006/html/5.2_how_tree_imp_soi.htm?n=69 [Accessed 8 Apr. 2021].
4. the Guardian. (2013). Native trees help wildlife – so why do councils plant so many exotic ones? [online] Available at: https://www.theguardian.com/environment/georgemonbiot/2013/aug/15/trees-native-exotic-wildlife-councils-insects [Accessed 8 Apr. 2021].
5. Bala, G., Caldeira, K., Wickett, M., Phillips, T.J., Lobell, D.B., Delire, C. and Mirin, A. (2007). Combined climate and carbon-cycle effects of large-scale deforestation. Proceedings of the National Academy of Sciences, [online] 104(16), pp.6550–6555. Available at: https://www.pnas.org/content/104/16/6550 [Accessed 8 Apr. 2019].
6. Pearce, F. (2019). Scientists Zero in on Trees as a Surprisingly Large Source of Methane. [online] Yale E360. Available at: https://e360.yale.edu/features/scientists-probe-the-surprising-role-of-trees-in-methane-emissions.
7. World Resources Institute. (2019). 7 Things to Know About the IPCC’s Special Report on Climate Change and Land. [online] Available at: https://www.wri.org/blog/2019/08/7-things-know-about-ipcc-special-report-land-and-climate.
8. Buis, A. (2019). Examining the Viability of Planting Trees to Help Mitigate Climate Change – Climate Change: Vital Signs of the Planet. [online] Climate Change: Vital Signs of the Planet. Available at: https://climate.nasa.gov/news/2927/examining-the-viability-of-planting-trees-to-help-mitigate-climate-change/.
9. Macmillan (2019). How much can forests fight climate change? [online] Nature.com. Available at: https://www.nature.com/articles/d41586-019-00122-z.
10. in (2019). Scientists Zero in on Trees as a Surprisingly Large Source of Methane. [online] Yale E360. Available at: https://e360.yale.edu/features/scientists-probe-the-surprising-role-of-trees-in-methane-emissions.
11. Marshall, M. (2020). Planting trees doesn’t always help with climate change. [online] www.bbc.com. Available at: https://www.bbc.com/future/article/20200521-planting-trees-doesnt-always-help-with-climate-change.