Photo by Noah Buscher on Unsplash

Not all Tree Planting is Equal

In recent years, huge areas of land across the world have fallen victim to the devastating effects of tree felling. The cost of this destruction to our ecosystems, our planet and our air quality is catasphrophic. But what if there was a new initiative that could, over time, help to repair some of the damage? Introducing tree planting and reforestation to areas of land that have been destroyed by humanity on a large scale not only mitigates global carbon emissions but also helps to restore dead or damaged ecosystems.

Reforestation benefits

Forests provide a magnitude of ecosystem services; these are the benefits humans obtain from  healthy ecosystems. Physical goods such as food, fuel and timber support economies and livelihoods  while ecological functions include habitats for wildlife, water and air purification, carbon storage and nutrient cycling, to name but a few. Trees also offer various social and cultural benefits; for example, certain tree species are highly symbolic and are believed to be sacred in some religions.

The growing increase of tree planting schemes 

The importance of forest ecosystems and their ability to capture and store carbon is becoming more prominent as global warming intensifies. The creation of tree planting projects has reached an all time high as countries around the world pledge to become carbon neutral by 2050 as an outcome of the Paris agreement. With the more eco-conscious of us looking for ways to neutralise our own carbon footprint, planting trees can be a great way of reducing carbon in the atmosphere as well as offering additional ecosystem services to the local community. 

Sustainable tree planting practices 

Planting trees is especially effective in tropical regions where they grow faster and capture carbon more quickly. Resources here though are often limited. Along with sustainable tree planting initiatives, The Word Forest Organisation works with the local community to select the most suitable varieties of tree species to plant. This ensures the survival of the newly established forest and encourages the return of native wildlife.  

The local community is an equal partner; gaining greater financial security and better quality of life through sustainable harvesting of tree bio-products, the planters remain dedicated to caring for the trees. This financial security would not be possible if tree felling occurred, which would leave degraded infertile land with a lack of monetary value for years to come. 

Not all tree planting is equal 

A recent study based on data from the Swedish National Forest Inventory and the Swedish Forest Soil Inventory found that all ecosystem services studied (tree growth, carbon storage, berry production, food for wildlife, occurrence of dead wood and biological diversity) were positively correlated to the number of tree species. Each tree species works alongside others to maximise the range of ecosystem services, therefore more ecological links are created, making the ecosystem more productive. The number of ecological niches, describing the role each species fills in its environment, therefore increases.

To ensure the trees’ survival and ability to store carbon for future generations, careful planning and management is needed. Without this, tree planting projects may harm the environment, resulting in ecological dead zones which can occur when the species of trees that are planted are unsuitable for the particular location. It’s important to understand the distinction between creating a sustainable carbon storing forest by planting mixed native and other suitable species which benefit the local community and building a monoculture ‘green desert’ which is destined to fail.

Monocultures of non-native species 

Planting mass numbers of a single tree species is known as a monoculture forest. Monocultures are often composed of a non-native species and characterised by their low cost and rapid growth. Since 1980, tropical monoculture forests have increased nearly fivefold. These types of forests degrade the land and cause the soil to become acidic, preventing the growth of other vegetation. In addition, they may store only half the carbon of a species-rich forest. 

Non-native species may become invasive and, over time, dominate the landscape, depleting water levels and nutrients and causing biodiversity to decline. Many studies have supplied evidence to suggest native wildlife is unable to survive in mono-culture forest environments. To restore biodiversity a specific range of food, nutrients and shelter are needed.

Unsuitable locations

Grasslands and savannas are biodiversity rich environments that lack tree cover. This makes them appear available for tree planting initiatives when, in actual fact, planting trees damages the ecosystem and disrupts its functionality. Increased tree cover results in a decreased frequency of fires, allowing additional vegetation to grow over the plants in the ground layer and reducing food availability for herbivores such as zebras. Wildlife species found in these environments have adapted to living in bright open spaces and will migrate away in response to increased tree cover. This has been demonstrated by numerous studies in South Africa and Brazil that recorded declining biodiversity as a result of planting on grasslands.

Even when a site is ecologically suitable for tree planting, the economic and social context of the area needs to be assessed to ensure the long-term survival of the trees.

Photo by Aliya Izumi on Unsplash

Examples of poor tree planting practice 

The Paris agreement has led to tighter environmental regulations for larger businesses, forcing them  to create and develop innovative ways to combat rising carbon emissions. Many large businesses have attempted to offset their environmental impact by planting trees, but it’s often done in a way that minimises time and costs. Some of these schemes involve little planning and aftercare, following a ‘plant and go’ approach, often with unachievable number targets. Unsurprisingly, as most trees take a long time to grow and require regular maintenance, the results can be very poor.

The trees often die due to lack of nutrients and/or their vulnerability to disease. Moreover, sites are frequently selected without any input from the local community and therefore the current use of the land – whether economic, cultural or spiritual – is disregarded. This can cause tension and ultimately lead to a lack of care for the trees. As research suggests, it is the locals, not the companies, who have the biggest and longest lasting impact on the establishment of forests. If companies want to make a real change, they need to prioritise a healthy and reciprocal relationship with the local community before embarking on a tree planting initiative. 

While China may be the world leader in forest growth, growing non-native species where they were not present before has caused the water table to decrease to alarming levels as a result of the trees sucking up the groundwater. This unsustainable scheme will have devastating environmental consequences in years to come.

Ireland has committed to planting 8,000 hectares of trees a year to increase forest cover. While this appears to be a fantastic scheme, afforestation efforts are currently dominated by monoculture plantations of the North American Sitka spruce, an evergreen. Here Sitka spruce creates dense, dark forests that are unable to support wildlife. Many residents fear that Ireland’s landscape is becoming lost to overseas investors attracted by the rapid return of Sitka plantations once felled. This not only destroys the natural functioning of the landscape, but means that family farms are being sold to private investors.

Thinking of supporting a tree planting project? 

Not all tree planting is detrimental! If you are interested in supporting a tree planting project, amazing! Every tree counts in the effort to restore our ecosystems and create sustainable ways of obtaining natural resources. Before you give, it’s vital to consider the charity’s methodology, to ensure your donation will have a positive and lasting impact.

Before donating ask yourself the following:

  • Does the project involve working with and benefiting the local community?
  • Does the charity plant a variety of species?
  • Are the trees native and/or suited to the location? Will they have a positive impact for local communities and biodiversity?
  • Are the trees safeguarded from future logging or fires?

By acknowledging these details, you can ensure your donation is one that keeps on giving, not just to the local community and wildlife but the local and the global ecosystem too.

Alice O’Grady and The Team

References
1. https://onetreeplanted.org/pages/why-trees
2. https://blog.ecosia.org/everyone-getting-tree-planting-wrong/
3. https://www.theverge.com/2020/1/31/21115862/davos-1-trillion-trees-controversy-world-economic-forum-campaign
4. https://theconversation.com/when-tree-planting-actually-damages-ecosystems-120786
5. https://theconversation.com/greenwashing-corporate-tree-planting-generates-goodwill-but-may-sometimes-harm-the-planet-103457
6. https://www.theguardian.com/world/2019/jul/07/the-wrong-kind-of-trees-irelands-afforestation-meets-resistance
7. https://www.theguardian.com/commentisfree/2018/oct/10/trees-ireland-biodiversity-sitka-birds-extinction
8. https://www.sciencedaily.com/releases/2013/01/130109081141.htm
9. https://www.independent.co.uk/environment/plant-trees-climate-crisis-where-greenhouse-gas-emissions-a9455671.html
10. https://news.mongabay.com/2008/09/monoculture-tree-plantations-are-green-deserts-not-forests-say-activists/
11. https://scienceblog.com/487742/chinas-reforestation-actually-causing-harm/
12. https://e360.yale.edu/features/why-green-pledges-will-not-create-the-natural-forests-we-need
13. https://theecologist.org/2020/feb/21/not-forest
14. https://www.theguardian.com/environment/2005/dec/23/frontpagenews.climatechange