Mitsui's Forests


Growing Forest to Protect Biodiversity

What is biodiversity? Here we explain how Mitsui cultivates forests that protect living organisms and their habitats.

Biodiversity means rich diversity and variety at the respective levels of gene, species, and ecosystem. If an area retains the original rich variety of its indigenous animals, plants, insects, microorganisms, and so on, and provides the physical requirements for their existence, it can be said to have high biodiversity.
But today, many animals and plants around the world are dwindling in number or gradually becoming extinct. With the habitats of a wide range of living organisms rapidly disappearing, businesses today need to take initiatives for the preservation of the biodiversity which is the foundation of our survival.
Through appropriate management of its forests, Mitsui is committed to making the social contribution of nurturing biodiversity and passing on a rich forest environment to the future generations.

Growing Forest to Protect Life

Mitsui's forests are made up of approximately 40% Forests for Regeneration and Harvest and approximately 60% Natural Forests and Naturally Regenerated Forests. These forests are divided into the following categories: Harvest - oriented Sustainable Cycle Forests; Natural Restoration Forests; Biodiversity Conservation Forests; Productive Naturally Regenerated Forests; General Naturally Regenerated Forests; and Other Naturally Regenerated Forests. Each category has its own set of management policies. Biodiversity Conservation Forests - areas particularly important from the viewpoint of biodiversity - form a new category created in 2009 and account for approximately 10% of Mitsui's forests.
Biodiversity Conservation Forests are further divided into the following four categories: Special Conservation Forests; Environmental Conservation Forests; Water and Soil Conservation Forests; and Cultural Conservation Forests. By conducting management appropriate to the special characteristics of each category, we aim to grow forests that are more strongly oriented toward the preservation of biodiversity.

Forest Management Zoning

Mitsui's approximately 444 km2 (44,417 hectares) of forests at 74 locations nationwide is managed according to the following categories:

Please scroll horizontally to look at table below.

(as of March 31, 2020)

Category Definition Area (km2)
Forests for Regeneration and Harvest Harvest-oriented Sustainable Forests Forests for the production and supply of lumber resources through the repeated cycle of harvesting, planting, and cultivating. 6,876
Natural Restoration Forests Forests to be restored as Naturally Regenerated Forests consisting of coniferous and broad-leaved trees. 10,586
Forests for Regeneration and Harvest, Natural Forests and Naturally Regenerated Forests Biodiversity Conservation Forests Special Conservation Forests Forests judged to have irreplaceable biodiversity value at the regional and national level and requiring stringent protection. 324
Environmental Conservation Forests Forests confirmed to support a large number of rare creatures whose habitat requires protection. 875
Water and Soil Conservation Forests Forests with plentiful water stocks that form a water resource, reduce the risk of natural disasters, or have other major socially beneficial functions which contribute to the safeguarding of the water supply and the preservation of ecosystems. 3,147
Cultural Conservation Forests Forests requiring protection due to the particularly high value of their "cultural services" - functions that nurture traditions and culture and form part of the "ecosystem services" that are dependent on biodiversity. 117
Naturally Regenerated Forests Productive Naturally Regenerated Forests Forests to be cultivated for tree species useful as a source of lumber. 1,822
General Naturally Regenerated Forests Forests not composed of productive species but to be cultivated for increased social value. 19,386
Other Naturally Regenerated Forests Naturally Regenerated Forests other than in the above categories. 1,271

Biodiversity Conservation Forests

Here we present Mitsui's forests that play a special role.

Four Biodiversity Conservation Forests

Areas with high significance from a biodiversity perspective are designated as Biodiversity Conservation Forests (which account for about 10% of Mitsui's forests) and further classified into four categories: "Special Conservation Forests," "Environmental Conservation Forests," "Water and Soil Conservation Forests," and "Cultural Conservation Forests."
This category classification allows for the more appropriate and carefully tailored conservation of biodiversity in specific forest areas.

Special Conservation Forests
Tashiro Forest, Fukushima Prefecture

Forests deemed to possess invaluable biodiversity at a regional and national level and will be closely protected.

Tashiro Forest, Fukushima Prefecture
This forest is part of Mt. Tashiro, which is located in Minamiaizu Town. It contains high-altitude moorlands in the mountain summit regions which have great academic value, and a portion of the forest including the wetlands is designated as part of Oze National Park.
Environmental Conservation Forests
Soya Forest, Hokkaido

Forests where biological value is concentrated, i.e., rare species, are identified. The habitat of these rare species is protected.

Soya Forest, Hokkaido
Mitsui's most northerly forest containing extensive stands of the Yezo spruce, one of Hokkaido's commonest coniferous trees, and home to the Ito fish, Japan's largest freshwater fish.
Water and Soil Conservation Forests
Nanba Forest, Niigata Prefecture

Forests with plentiful water stocks that form a water resource, reduce the risk of natural disasters, or have other major socially beneficial functions which contribute to the safeguarding of the water supply and the preservation of ecosystems. The 21st century has been referred to as the Water Century, indicating the increasing concern regarding the world's water resources. Recognizing the need to nurture forests that provide rich sources of water, Mitsui has designated 31.64 km2 (3,164 hectares) of its holdings as Water and Soil Conservation Forest, which is managed with attention to protecting water supplies.

Nanba Forest, Niigata Prefecture
The gateway to the Myoko Mountain Range, located in the municipality of Joetsu. With extensive beech woods that store water, the forest serves as a water resource that provides water to the region.
Cultural Conservation Forests
Saru Forest, Hokkaido
Kiyotaki Forest, Kyoto Prefecture

These forests are deemed to have high traditional or cultural significance to a region as a result of the ecosystem services from biodiversity. Mitsui will continue to take measures to protect these forests and to make the most use of them.

Saru Forest, Hokkaido
This forest is located in the Hokkaido municipality of Biratori, which legend holds to be the birthplace of the indigenous Ainu culture. Mitsui has concluded an agreement with the Biratori Ainu Association to protect and foster the Ainu culture.

Kiyotaki Forest, Kyoto Prefecture
This forest is located in Saga, Kyoto City. To allow the Kyoto Modelforest Association to undertake action to protect and nurture Kyoto's forests, Mitsui has concluded an agreement with the association and Kyoto Prefecture under which part of the forest is made available free of charge for a ten-year period from 2008. The forest will provide wood needed for torches and other materials used in traditional festivities such as the Daimonji Bonfire and the Kurama Fire Festival.

Scientific Evaluation

The biodiversity of Mitsui's forests - studied scientifically.

The Convention on Biological Diversity stressed the importance of addressing the preservation of biological diversity by undertaking quantitative evaluation of the level of attainment on the basis of scientific findings and principles. Mitsui carries out quantitative evaluation of biodiversity in model forests.

Quantitative Evaluation of Biodiversity (HEP)

In 2009, a quantitative evaluation of biodiversity was carried out under the Habitat Evaluation Procedures (HEP) by the Ecosystem Conservation Society - Japan at five model forest locations in Mitsui's forests, using animals as an index.
HEP is a method of quantitative evaluation of biodiversity used mainly in the United States. A number of wild animal species to serve as indices are selected in line with the surface area of the target site, the environmental conditions, the geographical location, and the rarity of the species. The level of biodiversity, including the past and future biodiversity, of the target site is then quantified in the form of a numerical value indicating the quality of the habitat for these index species, known as the habitat suitability index (HIS).
In the survey, the brown bear, Asiatic black bear, mountain hawk eagle, marten, and badger were chosen as index species. A prediction was then made of the change in the level of biodiversity from the past to the future, and a numerical value was assigned.
The results of the survey allowed the level of biodiversity for each model forest to be assessed, and additionally provided basic data for forestry operations contributing to biodiversity, which indicated for instance which areas of Forests for Regeneration and Harvest should be prioritized for restoration as Naturally Regenerated Forests.
Examples of zoning: (1) (2) (3) (4) indicate zones in order of priority for restoration as Naturally Regenerated Forests. The deeper the red, the higher the priority for restoration as Naturally Regenerated Forests.

Niwan Forest
Sando Forest
Kiyotaki Forest

AA+ Awarded in JHEP Certification

JHEP certification is a certification system established in December 2008 by the Ecosystem Conservation Society - Japan. This certification system makes a quantitative evaluation of the level of biodiversity from the viewpoint of animals and plants in a ten-level ranking system from AAA to D. The evaluation quantifies biodiversity in the 30 years before the base year (the year of acquisition of the land or the year in which the application for evaluation is made) and in the 50 years after the base year and compares the two periods. This allows scientific proof to be given of the contribution of an enterprise or other agent to the preservation and enhancement of biodiversity.

In September 2010, an evaluation was carried out in the Kiyotaki Forest in Kyoto which covered not only the Asiatic black bear and other animals (evaluated species) but also plants. As a result, the second highest ranking possible (AA+) was awarded. This represented the first such ranking for a Japanese forest under this certification system and gives scientific proof that in the approximately 30 years of Mitsui's ownership of the Kiyotaki Forest, the level of biodiversity has been raised in keeping with the characteristics of the region. Going forward, we will continue with the management policy implemented so far, preserving the remaining native vegetation of the area and gradually restoring the Forests for Regeneration and Harvest areas of Japanese cedar and Japanese cypress to Naturally Regenerated Forests.

At COP10 (Convention on Biological Diversity), effective and urgent action was called for to halt the loss of biodiversity by 2020. Further, the convention emphasized the importance of quantifying and monitoring the level of biodiversity on the basis of scientific findings and principles. Given this background, we believe that our acquisition of this certification demonstrates the beginning of a new model of forest management for Japan in the future.