Living blocks based on Japanese indigenous knowledge to regenerate a soil and forms urban micro-forests in the city

Comoris BLOCK was designed by ACTANT FOREST as a kit for installing “micro-urban forests” in vacant spaces. This work was exhibited as an installation in the exhibition ‘Material, or ’ at 21_21 DESIGN SIGHT in Tokyo, for four months since July 2023.

Unlike concrete blocks, this work consists of blocks of familiar materials such as rice bran, sawdust, and bamboo charcoal, into which trees and grasses have been planted. These blocks will eventually revert to soil, but now they serve as kits to bring a new forest ecosystem into urban life. The material partake of wisdom is derived from the diversity of biological forms as they generate new wooded spaces. They are, so to speak, living bio-blocks that fulfill their mission of regenerating vegetation on land by being decomposed by non-human entities such as microorganisms, insects, and plants.

ComorisBLOCK 02 Keizo Kioku

ComorisBLOCK 03 Matthew Masayuki Crilley

To achieve this goal, ACTANT FOREST references indigenous Japanese techniques. In the past, Japan had many innovations that emphasized resource recycling and living in harmony with nature. By combining this local knowledge and co-design methods into a single package, anyone can easily install a “micro-urban forest" with just a shovel, starting at a scale of approximately 1 square meter. The spread of “micro-forests" as a multi-species environment in the city will bring biodiversity and resilience to urban life.

The installation is divided into indoor and outdoor museum areas. The exhibition begins indoors, where the materials that make up the blocks are scattered and tell the story of how the blocks are disassembled to form a micro-forest in an outdoor space. Visitors can observe the process as if they were strolling through a forest. The concept of the Comoris BLOCK asks what the relationship between people and nature will be like in the future from an anthropological perspective.

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Referring to indigenous wisdom

Comoris BLOCK is a prototype to explore the role of design in the era known as the Anthropocene, expanding the stakeholders from human to more than human include plants, animals, and microorganisms. To this end, it references the forest management techniques practiced by premodern Japanese farmers. They were skilled in gathering resources from the forest, utilizing them, and returning them to the forest again, thereby circulating resources and regenerating the environment. It is a complex system that is not an act of exploitation and consumption, but a practice that can be realized using materials that are all around us.

How can we make this technique, which is currently being forgotten, more versatile in modern life? After several years of research, we arrived at the output of designing their wisdom in the form of a block. The basic materials utilized are all organic and therefore biodegradable. First, standard materials such as fallen leaves and rice bran are solidified. They serve as nutrients and stimulate the activity of microorganisms. Second, materials such as rice husk ash and bamboo charcoal, which have porous structures, promote the circulation of air and moisture. At the same time, the small spaces in the porous structure provide a home for microorganisms. All these materials are formed into a single Minecraft-like block by tabuko, a natural wood powder used to make incense in Japan.

ComorisBLOCK 06 Matthew Masayuki Crilley

ComorisBLOCK 07 Matthew Masayuki Crilley

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As a multi-species hotel

The landscape created by combining blocks according to the shape of the site is for people to enjoy themselves, and at the same time, it functions as a place like a hotel for other species more than humans, such as plants and insects. The materials provide nutrients and an environment conducive to the growth of microbiota and mycorrhizal fungi. Trees, plants, and flowers that coexist with microorganisms and mycorrhizal fungi grow in the holes drilled in the blocks. Insects and birds gather in this environment. The blocks form a placemaking, hotel-like environment for microorganisms, mycorrhizal fungi, earthworms, centipedes, frogs, pollinators, trees, plants, flowers, and humans. The meaning and use of materials change from moment to moment, depending on the local climate and the activities of the organisms, and the usefulness of the block is determined by the entanglement of various perspectives and agencies. When the blocks decompose and disappear through its use by various organisms, the soil and the ecosystem around the blocks are regenerated.

ComorisBLOCK 15 Matthew Masayuki Crilley

Even though the exhibition was held in a concrete enclosed courtyard in the middle of Tokyo over the course of three months, it attracted a wide variety of species from the surrounding environment. Small lizards, spiders, and ants became permanent residents, and dragonflies and stinkbugs could also be observed.






As a tool for co-design

In the pre-modern era, all local farmers entered the forest as commons and worked together. This block also references the production process, which differs from the current design. We designed a simple shape and DIY production process that can be flexibly configured to fit any shape of land so that local citizens can easily participate in its construction. This project will enable collaborative production even in urban areas by providing a workshop-style mold that anyone can make.

In addition to the basic materials mentioned above, unique recipes can be created by adding materials available in each region. For example, by mixing construction site waste and coffee grounds, which are readily available in Tokyo, it is possible to create blocks for resource recycling in the city. In the case of forests, by mixing the ash from exotic plants that have been burned to exterminate them, a block for environmental improvement can be created. By mixing unique materials, a block with a regional character in which resources circulate within the area can be produced. It can be said that this block is rooted in the land, in which a unique place is created by the community, and the local vegetation and ecosystem can be regenerated while using local materials.

ComorisBLOCK 11 Matthew Masayuki Crilley

ComorisBLOCK 13 Matthew Masayuki Crilley

ComorisBLOCK 12 Matthew Masayuki Crilley

ComorisBLOCK 14 Matthew Masayuki Crilley

Next steps: open-source recipes

After the exhibition, the micro-forest created by the blocks was transferred to the forest in Minami-Alps. We plan to observe how they change in a forest ecosystem over a large time scale. The blocks will show their effects when nurtured for such a long period. In this era of the Anthropocene, designs that confront issues for an open-ended period are required.

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As a future development, we would like to make the block recipes open source. The ability to freely create various recipes means that the effects of the blocks can be freely designed. A seed bomb-like function can also be added to the embedded seeds. In this exhibition, we created the most standard blocks, but it will be possible to add effects that match the target site depending on the materials and seeds to be mixed. For example, we could make a block to form a garden for pollinators, a block with plant seeds for bioremediation to clean up soil pollution, or a block for a food forest. Various recipes can be created, depending on the location. ACTANT FOREST would like to experiment with the creation of such kits and recipes in the next step.

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  • Support: Hiroto Okuda (Poietica LLC.)
  • Photo: Keizo Kioku, Matthew Masayuki Crilley