blue sky and trees mixed together
Photo credit: Ruth Maclennan

Ruth Maclennan and Treeline

Treeline, the Climate Emergency and COP 26

We invited you to help create a collective film, Treeline. The film featured forests from across the world, highlighting the impact of the climate emergency on the world’s forests.

The film was commissioned by Forestry England and Film and Video Umbrella and was presented online, coinciding with COP 26, the UN’s climate change summit that was held in November 2021 in Glasgow.

What is the film, Treeline?

The multiple, continuous horizontal panning views in Treeline aim to show the horizontal spread of forests of all kinds across the earth, and also to evoke the way trees sometimes thrive and take over land when left alone. The film aims to be a kind of collectively imagined and constructed forest ‘corridor’. 

The treeline suggests the lines that humans draw, in the landscape and through time, lines they create and cross.  Shifting treelines are also a warning about the danger of destroying forests for biodiversity loss and a heating planet.

Treeline also refers to the treeline in nature that varies with altitude, latitude, and temperature.  The treeline is the blurred boundary where trees are no longer able to grow because it is too cold, or they receive too little light, or not enough nutrients. After this point, tundra grows – in high-altitude alpine, arctic and subarctic environments. As temperatures and atmospheric carbon dioxide concentrations rise, treelines will move.

Climate change

Some of the treelines that matter most  are manmade: clear-cutting in the Amazon and the destruction of forests for building cities and infrastructure. Also, less dramatically, ‘treelines’ are visible in the rows of planted trees, the manmade edges and boundaries of forests and woods. 

Some treelines between ecosystems – markers of destruction and reclamation – may also represent zones of conflict. The traces of forest and tundra fires sweeping across continents, or of floods washing trees away, will also appear in the film, tracing topographies of destruction, and sometimes, recovery and regrowth.

Tree destruction in the Amazon rainforest
Treeline art
Nicholas Noyse


The soundtrack of the film Treeline made use of field recordings recorded around the forests and trees where the footage is shot and offers a sweep across the globe plus the individual, multispecies, voices of particular forests and wooded environments. 

Location sounds and voices such as birdsong, leaves rustling, tree felling, machines whirring, human and animal footsteps and voices,  were worked with alongside those sourced internationally to produce a polyphonic soundscape.   


Ruth Maclennan is an artist. Maclennan’s recent films and photographs explore how the climate emergency has irrevocably transformed ways of seeing and understanding landscape and place – both for their inhabitants, and as representation. 

Her films, CloudberriesCall of North and Hero City shot in the Russian Arctic premiered at the London Film Festival, and her solo exhibition Icebreaker Dreaming was at Pushkin House in 2020. She exhibits internationally in exhibitions and film festivals.  Since April 2020 she has contributed to The Crown Letter and LUX Artists’ Moving Image distributes her films.  

Treeline Ruth Maclennan

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