End of the walk
Below you will find the audio and text of the walk !
Have a good adventure !
We have reached the end of the walk. Thank you for participating and joining until the end of this adventure. Thanks also for having opened your ears and your eyes to discover this peculiar organism and its diversity.
On the tree in front of you, you can find most of the species we saw during the walk. Can you name and differentiate between them ?
All the pictures shown below on the diaporama of this article are photos taken by the author (otherwise stated) and are under a CC BY-SA 4.0 license.
There is Physconia grisea, a species seen earlier at the Meeûs Square.
We also find Punctelia subrudecta with its small granules and its blue-grey thallus.
Phaeophyscia orbicularis is a species that we have already seen and identified on trees. A quick refresher on this species: it is often seen on walls, on tree trunks in an environment rich in nutrients (like carbon dioxide and nitrogen). This lichen is pale grey in colour, and sometimes darker (brown black). The lichen has soralia (asexual reproductive structures see here for more info) all over its thallus and sometimes on the margins of the thallus. The lower surface is black with dark coloured rhizines (small attachments).
If you look a little higher up the tree, you can also appreciate the little porcelain sculptures that Franck Sarfati has placed on the tree to remind us of the symbiosis and to draw our attention to what we often don’t take the time to observe. The question he asks through his art is: “Has human become the greatest parasite of all?” Franck has placed these “symbiotic” sculptures in several parks in Brussels, you can find more information about his work here.
I hope this walk has made you think about the presence and importance of lichens in the urban ecosystem and in our understanding of natural phenomena. You will have noticed that our ideologies influence what we see and what we want to see (like Schwendener who talked about the alga being the “slave” of the fungus – see information in the Leopold Park on symbiosis).
Current discoveries about fungi and other organisms, such as lichens, reveal ways in which beings live on our planet. Perhaps the crises that are coming (social, ecological, and political) will trigger changes in our perception of the world, deconstructing a nature/culture dualism, and rethinking the place of human in a world made of complex networks of interactions.
In any case, I hope this walk is a step towards discovering the city in another way, decolonising urban spaces from anthropocentric ideas and seeing them not as only human spaces, but as complex interactions of different species.
Identifying more lichens
Your journey into the world of lichens is only beginning… They are many more lichens to discover. The identification guide below is a first start to identifying other lichens than the ones we saw on this walk.
Otherwise, if you are keen, it is worth investing into a proper identification book, here are some suggestions:
- A great book in English (the one I use), which helps identifying lichen species in Great Britain, but also often found in mainland Europe:
Dobson, F. S. (2018). Lichens: an illustrated guide to the British and Irish species. Richmond Publishing.
- An identification book in French, for epiphytic (on branches) and corticolous (on bark) lichens :
Van Haluwyn, C., & Asta, J. (2014). Guide des lichens de France. Lichens des arbres. Belin.
- An identification book in French, for terricolous (growing in the soil) lichens :
Van Haluwyn, C., Asta, J., & Boissière, J. C. (2014). Guide des lichens de France. Lichens des sols. Belin.
Un petit quizz
I would appreciate your feedback – positive and/or negative – on the walk. You can access a questionnaire here. It won’t take you more than 5 minutes! Thank you in advance.
Thank you again for your participation. If you find other lichen species that you have identified, or would like help with identification, please contact me at firstname.lastname@example.org.