TreeTalk in Brussels

Spring is upon us and the trees are greeting us in full bloom. What better way to marvel at the new leaves and flowers serenading Brussels’ streets than to enjoy a guided route of the trees. Inspired by the London-based TreeTalk, we have mapped a walk to enable city-dwellers to discover the urban forest.

TreeTalk is an online mapping tool featuring the location and species of more than 700,000 trees in London. After the user inputs the starting postcode, the software identifies trees and creates a walk assisted by facts and information about each tree. The mission is to inform and explain the benefits of urban trees and green infrastructure. As this software is not (yet) available in Brussels, we decided to create our own mini TreeTalk route.

Before starting the walk, let us first share the root of our love for street trees and why you too should branch out to support urban forests. We know that trees in urban areas are hugely important to those living in the ‘concrete jungle’ for health and wellbeing. Trees also offer a multitude of environmental benefits to communities:

• Trees hold up to 120kg CO2 during their lifetime and thus purify the city air
• Trees filter up to 20kg of particulate matter per year such as ozone, sulphur dioxide, etc. and filtering dust, ash, pollen
• Trees provide shade which acts as air conditioning on an urban scale and prevent the heat island effect
• In winter, trees form a (wind) screen and thus limit the influence of cold wind and leads to less heating energy consumption
• Trees are hiding places for animals and insects thus enabling the conservation of urban biodiversity
• The planting of trees in rows reduces the reverberation of traffic noise of traffic noise on facades

The City of Brussels made a plan to develop and protect its public tree heritage. The objective of the 2020-2030 is to increase the presence of trees in Brussels City and thereby make the city more resilient and pleasant to live in. The drivers of this project are incredibly passionate about urban trees,for example they powerfully state that “For the tree in the urban environment is above all a living being: the vision of a tree as an object, at worst likened to a vulgar piece of urban furniture, must be a thing of the past.” Overall, the initiative aims to increase the public knowledge of street trees and plant trees wherever possible by 2030.

1. Crateaegus laevigata - Hawthorn, Midland

→ Location: Corner of Rue Ernest Solvay
A small dense and bushy tree that is indiscriminately dispersed across many streets in Brussels. It is tolerant of exposed, polluted and damp sites thus an excellent match to an urban context. It is popular amongst wildlife, the birds in particular enjoy the fruits it bears.

2. Acer platanoides - Norway Maple

→ Location: Intersection of small green space
A large tree, often reaching heights above 20m, is widespread in central Europe and eastwards in the Ural Mountains. It is a fast-growing species, able to grow in a wide range of soils and habitat conditions. This species has been used extensively as an ornamental, shade and street-side tree because of its attractiveness, colourful foliage and large, spreading crown, in combination with its tolerance of urban conditions.

3. Aesculus hippocastanum - European Horsechestnut

→ Location: Beside the traffic lights on Rue du Trone
A broad-crowned deciduous tree amongst around ten others of the same species provide both shade and colour along the street. The large leaves are gathered in 5-7 leaflets with both white and red/pink flowers. Although, don’t be tempted by the beauty of these flowers, they are in fact highly poisonous to humans!

4. Fagus sylvatica - European Beech

→ Location: Inside the Parc Leopold
A large tree, it is capable of reaching heights of up to 50m tall and 3m trunk. Beech is widespread across Europe: it can be found from Sicily in the south to Bergen in southern Norway. This particular tree towers above the others in the green corner, its burgundy leaves drape across the park offering a source of shade during the warm days ahead.

5. Carpinus betulus - European Hornbeam

→ Location: Place du Luxembourg
Trimmed to perfection this tree decorates the highly prestigious Place du Luxembourg. It is described as “gnarled and mighty” with egg-shaped, double serrate leaves that are bright green and strong as they offer year-round leaf cover, hence a winter haven for wildlife.

6. Aesculus hippocastanum - European Horsechestnut

→ Location: Back entrance to Parc Leopold
A magnificent tree with a chaotic assembly of branches growing in each and every direction, their presence is seemingly alive. It is unsurprising that its nickname is ‘The Octopus’ given the extravagance of its reach. It is the same species as the tree found at stop three, however this particular one is far more mature and thereby grander - notice the similarities and differences in their appearance.

7. Platanus orientalis - Old World sycamore or Oriental plane

→ Location: To the left of the steps leading back up the hill
This deciduous tree can grow up to 30 m by 30 m at a fast rate. he tree is mainly used for ornamental
purposes, particularly given its characteristic speckled stem and its great tolerance to urban stress. A
fun fact to conclude on is that in Iran, this species is used in traditional medicine!

8. Tilia × Europaea - Common Lime

→ Location: Corner of Rue Goffart entering into Matonge
This tree is a naturally occurring hybrid between Tilia cordata and Tilia platyphyllos. It occurs in the wild in Europe at scattered localities wherever the two parent species are both native.

It was a purposeful decision to have a long stretch between the final two trees, the reason was to show the disparity between a space with an abundance of trees and one where it was lacking. Did you notice this difference, and if so how did the change in tree population impact your walk?

Access to nature should be a universal right. Tree planting in urban contexts enables equality and benefits far beyond the aesthetic and beauty of the green treasures. We hope that this short walk has opened your eyes to the unsuspected dendrological richness of the Brussels Region and you will walk through the streets with more wonder and curiosity.

Written by Alice Sparks, May 2022

Sources:

Conifers.org. 2022. Pinus nigra (schwarzkiefer) description - The Gymnosperm Database. [online] Available at: <https://www.conifers.org/pi/Pinus_nigra.php> [Accessed 2 May 2022].

Brussels.be. 2022. 2020-2030 Tree Plan. [online] Available at: <https://www.brussels.be/2020-2030-tree-plan> [Accessed 2 May 2022].

B.V., B., 2022. Carpinus betulus | TreeEbb | Online tree-finding tool | Ebben Nurseries. [online] Ebben.nl. Available at: <https://www.ebben.nl/en/treeebb/cabetulu-carpinus-betulus/> [Accessed 2 May 2022].

Forest.jrc.ec.europa.eu. 2022. [online] Available at: <https://forest.jrc.ec.europa.eu/media/atlas/Fagus_sylvatica.pdf> [Accessed 2 May 2022].

Pfaf.org. 2022. Platanus orientalis Oriental Plane, Oriental planetree PFAF Plant Database. [online] Available at: <https://pfaf.org/user/Plant.aspx?LatinName=Platanus+orientalis> [Accessed 2 May 2022].

Secretariat, 2022. Platanus orientalis - EUFORGEN European forest genetic resources programme. [online] Euforgen.org. Available at: <http://www.euforgen.org/species/platanus-orientalis/> [Accessed 2 May 2022].

Wood Wide Web. 2022. WOOD WIDE WEB "The octopus". [online] Available at: <https://www.woodwideweb.be/en/atlas/210.html> [Accessed 2 May 2022].