Ulf Mejergren, a Swedish architect and artist, and Antti Laitinen, a Finnish artist, gathered fallen branches from a forested area outside of Nykvarn, a small city southwest of Stockholm, in April of this year. The pair used the wood scraps to weave a structure around a tree, creating a warm haven in the thawing spring landscape.

That structure was the first installment of the ongoing One Tree Four Seasons project, in which the artists gather natural materials from the surrounding area to create site-specific land art.

During the summer, hay from a nearby field was used to insulate the walls and floor as well as create seating inside the enclosure, while the lush treetop served as roofing. In the fall, the same leaves wrapped the structure’s round opening in an upward swell and piled into a colorful path.

Mejergren tells Colossal that the fourth and final iteration will be completed in December, though this is subject to weather. For updates, follow him and Laitinen on Instagram. (Image courtesy of This Isn’t Happiness)