To avoid unforeseen consequences when planting new forests, it is recommended to consider five things: evaluating the potential and risks of planting non-native trees; avoiding planting without a plan for seedling maintenance and survival; remembering the essential difference between planting a monoculture and maintaining a forest as a monoculture; if possible, avoiding planting in areas that are unique habitats or have high biodiversity value, as well as avoiding planting on land that is essential for production in the region.

Risks of planting non-native trees and their assessment

One of the most common problems associated with large planting projects is the planting of non-native trees. They can disrupt the balance of local ecosystems and lead to unintended consequences, such as reducing biodiversity and degrading soil quality. In some parts of the world, eucalyptus is planted due to its rapid growth and timber production potential; however, in many of these regions, eucalyptus is not a native species, and its introduction has caused the displacement of native species and even the depletion of water resources. For example, a study on eucalyptus plantations in Argentina shows that they have far fewer bird species and undergrowth plants than native forests, and even fewer than other intensively managed lands, such as blueberry and citrus plantations. To avoid such risks, it is recommended to evaluate the options for planting native tree species. In most of Europe, this field is also regulated by legislation, and forestry laws often restrict the tree species allowed or prohibited for planting. Planting native trees helps to make the forest as attractive as possible to various other species, thereby increasing the forest's biodiversity.

Seedling maintenance and survival plan and its development

Another challenge that can arise in afforestation projects is the lack of a seedling maintenance and survival plan. If an appropriate plan is not developed, young trees may not receive the necessary care and attention, leading to a high mortality rate. In some projects where trees are planted without proper soil preparation, they die due to a lack of water or nutrients. In other cases, trees may be planted too close to each other, causing overcrowding and competition for resources. Conversely, in some tree planting projects, seedlings are simply abandoned after planting, which has led to heavy losses because the young trees lose the battle against weeds and grass or are simply eaten by elk. It is important to remember that seedlings must be cared for, especially during the first three years after planting. This also includes weed control and protection against elk and other herbivores that enjoy eating young trees.

The difference between planting a monoculture and maintaining a forest as a monoculture

Many have heard that planting monocultures is bad. This is quite self-evident, as a forest that contains only one species is not biologically diverse and is more vulnerable to pests and fires. It is important to remember that there is a significant difference between planting a monoculture and maintaining a forest as a monoculture. For example, we may choose to plant spruce seedlings, knowing that the surrounding birches will shed seeds after a few years and that birches will naturally regenerate among the spruces. Although we are primarily planting one species in this case, we are still creating a mixed forest by also encouraging the growth of other species. Furthermore, in some forests (e.g., pine), the trees are homogeneous, which is compensated for by a rich range of undergrowth species, such as bilberries. Encouraging species diversity, both through planting (if possible) and through ongoing management, can also be achieved by planting fewer trees to promote natural replenishment and avoiding the clearing of other species during thinning operations.

Assess the land intended for afforestation

Not all land areas can be forest land, and not all areas should be. There are various unique biomes, such as alvars and highly diverse semi-natural grasslands, which are valuable in their own right. Converting them into forest land could actually reduce biodiversity. Therefore, before afforestation, it is important to carefully assess the land and ensure that we are only planting on land that would be useful to convert into forest. The best way to do this is through a careful, data-driven approach, which is why Arbonics has developed its own internal platform that identifies specific high-value areas that are not suitable for afforestation. As we continue to refine the solution, we are constantly supplementing information about the land so that these decisions are even more accurate and based on data. Assess the land intended for afforestation and check whether it is included on a list of high-value habitats. Do not plant in ways that could destroy existing biodiversity.

Production essential to the region

Although it might be tempting to use the most productive agricultural land available for afforestation because it means faster tree growth and consequently a larger amount of sequestered CO₂, we cannot ignore the fact that land is used for various needs, and one of the essential ones is food production. If we convert all agricultural land into forest, a reduction in food supply could occur. To avoid such risks, only land suitable for afforestation should be used, and a risk assessment should be carried out to ensure that we are not harming food production. Afforestation plans should be created on land areas whose potential is currently not being fully utilised. The best land for afforestation is low-quality or abandoned agricultural land and pasture; by planting trees in these areas, we can avoid potential conflicts with food production. It should be added that one must also not plant on land areas that have other historical or cultural value; for example, Stonehenge would certainly not be suitable for afforestation.