London plane

Plane trees: facts and stories

If you want to go unnoticed in the city, dress up in a camouflage outfit and stand against a plane tree’s trunk. This tree is commonly found in public places, but people rarely take much notice of it despite its magnificent bark. Multicoloured with greens, browns, ochre and beige, this bark flakes off in patches with curved edges, creating pretty raised sections on its smooth trunk.

Look around a plane tree’s base and your eyes will be treated to something of an abstract painting or puzzle with numerous colours and textures. The patterns in the bark may well spark inspiration and set your imagination running with various thoughts...

An Ancient Greek legend recounts how the bark of plane trees helped Cadmus to introduce the Phoenician alphabet to the Greeks (who later adapted it into the Greek alphabet). Cadmus used patches of bark for writing, and for the creation of simple signs. One day, Cadmus departed on a long journey to look for his sister, Europa. Throughout his time on the road, he left messages written on pieces of bark from plane trees. This helped with spreading this type of script. The legend doesn’t specify whether Cadmus used raw bark fragments or made them into scrolls. One thing’s for sure though: he wrote on pieces of the tree’s bark, not directly on the tree trunk.

Did you know?

Most trees keep their bark for their whole lives. Much like skin, this enveloping layer serves as an outer barrier to protect the tree. Bark shields the tree against sunburn, frost and cold snaps. It is also a physical barrier against certain types of fungi and insects (which can carry diseases), as well as against other invasive plants.

So, why do some trees like planes lose their bark (referred to as flaking off/desquamating)? Scientists have conducted research into this and one of their hypotheses is that plane trees lose pieces of their bark as a system of defence. By having their bark flake off in pieces, fungi and insects aren’t given enough time to take hold and infest the tree’s trunk. This defence strategy therefore sees the tree ‘change its skin’ every year.

Just below this layer of ‘skin’ on the trunk and above-ground roots, there is the living part of the trunk, which is susceptible to injuries that risk the health of the whole tree. Therefore, it’s important to always treat a tree’s bark as gently as you would an animal’s skin, no matter if it’s thin or thick; cracked, furrowed or grooved; smooth or rough; hard or soft.

The benefits of plane trees

It’s hard to find a tree that’s more useful in towns and cities: it performs numerous services and conducts all of them efficiently.

Very commonly seen around cities, this familiar tree species is an all-round marvel. It is a real champion when it comes to absorbing air pollution and filtering fine particles from the air. It is very good at regulating its surrounding climate: creating a cooling effect and adding pleasant humidity. It also casts light shade. All of this is done in a gentle, discrete fashion.

Plane trees are known for their great resistance to all the stresses that arise from urban environments: air pollution, compacted soil, dryness, and drastic trimming. They are some of our best allies in making urban life more liveable, whether planted in playgrounds, public squares, or along busy avenues.

How to recognise a London plane

Bark

often a combination of three colours: grey-green, ochre-brown and cream; with large patches of scales with curved edges as they start to flake off (desquamate), creating a camouflage pattern

Leaves

large (12–25cm), with indents forming 5 parts (lobes) arranged like fingers on a hand (palmately lobed); Coarsely serrated edges; fall from the tree in autumn (deciduous)

Foliage

soft green in spring/summer; ochre in autumn; and no foliage in winter

Fruit

achene, ball-shaped and spiky, with felty seeds like pompoms; clearly visible on the tree in winter

Specifics about this tree

London plane trees are so common around the city that people barely notice them. They are thought of as urban furniture. Especially on long avenues and in public squares, where they are sometimes shaped like coat stands. This is not the case with this specimen. Its majestic and comforting presence dominates the back section of Plaine de Jeux Renier Chalon. It grows overhanging the swings. Do you think the youngsters playing here take notice of it?

Over time, this tree’s bark has become more uniform, losing its multicoloured patterns. The bark is now more of a light brown shade. The little patches flaking off are less visible because they fall off very quickly. The big roots still show some camouflage patterns though. When children play hide and seek, concealing themselves behind this tree’s trunk, they will certainly notice these patterns. It would be quite fun to use a pencil and paper to take an imprint of these patterns!

In summer, the tree’s giant foliage provides shade for everyone to sit, chat, play and enjoy the swings. This plane tree makes the atmosphere here feel softer and cooler. It adds moisture to the air, which is pleasant for the skin and lungs, and it functions as a gigantic air conditioner during heatwaves (which seem to be more severe with each passing year). Without this tree, and its brothers next to the basketball court, this playground would be scorching in the summer months (something of an urban heat island). This plane tree reminds us of how essential it is to our wellbeing!

(Story and photos created by Priscille Cazin- Sylvolutions)

This portrait is:

- Enriched with an illustration from the Belgian Federal State Collection on permanent loan to the Meise Botanical Garden.

- An initiative of Christos Doulkeridis, Mayor of Ixelles , Audrey Lhoest, portfolio holder for Environment, Green Spaces and Planting, and Tourism and the Ixelles Communal executive