Forests perform a variety of functions for the public good, including erosion control and water control, cultivating water resources, curbing global warming by absorbing CO2, and preserving biodiversity. For these functions to work effectively, proper forest management is crucial.
The Sumitomo Forestry Group believes that sustainable forest management is necessary to ensure that timber resources are available in perpetuity, and is advancing initiatives both in and outside Japan.
The Sumitomo Forestry Group owns forests with a total area of 42,868 hectares within Japan. Outside Japan, it manages forests with a total area of approximately 200,000 hectares. The functions of forests that serve the public good can be enhanced by appropriate forestry management including weeding, pruning, and thinning.
Forests absorb CO2 then retain it as carbon – or “carbon stock.” The carbon stock of the Sumitomo Forestry Group forests in Japan was 10.74 million t-CO2, and the carbon stock of plantation forests overseas was 3.62 million t-CO2.
In fiscal 2011, the Sumitomo Forestry Group harvested approximately 560,000m3 of trees. The harvested trees were milled and processed, then provided to the world as a variety of applications, including housing and furniture. In some cases, for example structural members used in houses, the timber will be used for decades.
Even after trees are processed into products, the wood continues to retain CO2 as carbon. Thus, it can be said that using wooden products and building wood-construction homes are activities that “Create Forests in Cities.”
One Sumitomo Forestry Home house has a carbon stock of about 22.6 t-CO2. The carbon stock of all houses constructed by the Company in fiscal 2011 (9,007 houses) totaled approximately 203,000 t-CO2.
Wood products can still be used effectively even after they have served their purpose. For example, in the case of wood-construction homes, the lumber can be re-used after demolition as wooden materials such as boards.
Wood chips resulting from this process of re-use, and wood that has served its purpose as a wooden product, can still be used as wood fuel. This is called cascade usage and is a way to use wood completely and totally. In this way, carbon is retained until wood products are used as biomass fuel to create electricity. At this point, the CO2 released from burning the wood is the CO2 that was absorbed during the tree’s growth process, so the CO2 in the atmosphere has not been increased during the life cycle of the tree.
Just harvesting trees and using the timber means forestry resources will be diminished. Sumitomo Forestry always plants and cultivates new trees after harvesting trees to ensure sustainability of forest resources.
In fiscal 2011, Sumitomo Forestry planted forests in Japan with a total area of approximately 54 hectares and 13,905 hectares overseas. From a carbon stock perspective, during the time wood products used in cities are retaining carbon, newly planted trees grow, absorb CO2, and retain carbon. By promoting operations that encourage greater use of timber resources through the structural application and incorporation of wood. Company-owned forests and the carbon retained in the homes built by Sumitomo Forestry thus increase the carbon stock and contribute to counteracting global warming.