uma and antti laitinen nestle sauna within an alder tree
Following the first, second, and third parts of their art series, the fourth and final installation in Ulf Mejergren (UMA) and Antti Laitinen’s ‘One Tree Four Seasons’ unfolds as an ode to winter. Surrounded by a bed of snow and a blanket of fog, a solitary alder tree has been enveloped in plastic and transformed into an outdoor sauna. Set against a quiet field in Stockholme, the tree’s wrapping retains heat and steam for its inside, while blending in with its landscape on the outside. Making use of locally available natural materials, the sauna is heated with wood from the site and creates the illusion of a white floating volume amid a bare tree crown as the smoke rises.
season IV amid a blanket of snow and mist | all images courtesy of Ulf Mejergren Architects (UMA)
‘one tree four seasons’ series comes to a cyclical end
‘One Tree Four Seasons’ is an ongoing collaborative project between Swedish architect and artist Ulf Mejergren and Finnish artist Antti Laitinen who have been experimenting with changing the alder tree’s form in various expressions in relation with each season. From one tree, duo has now made four different projects, bringing the project to a natural cyclical end making each installation into a reflection of its particular time. The various interventions also took advantage of the tree’s different seasonal appearances to reveal immersive and interactive experiences.
Ulf Mejergren (UMA) and Antti Laitinen with Season IV
a lightweight structure creating the illusion of floating drapes
a sauna immersed in nature
the sauna is heated with wood from the site

the plastic envelope retains heat and steam for its inside, while blending in with its landscape on the outside
project info:
name: One Tree Four Seasons – Season IV
designer: Ulf Mejergren (UMA) + Antti Laitinen
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edited by: ravail khan | designboom