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HomeFeaturesの中のExploring the Possibilities of Lumberの中のBuilding Roads for Forestry and the Future of the Woods

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Exploring the Possibilities of Lumber

Building Roads for Forestry and the Future of the Woods

February 18, 2013

Mr. Okahashi, who owns and manages forests in the forests of Yoshino in Nara Prefecture—home to the renowned Yoshino cedar wood—also helps build forestry roads used by forest thinning equipment and the trucks that haul thinned timber. As he discusses the reasons for building these roads, his tone and manner convey his strong desire to preserve the Yoshino’s forests and forestry traditions for future generations.

The sturdy trunks of 100 to 200-year-old trees survive to this today

The Yoshino forests are in a forestry district that has now been in use for some 500 years. A great deal of local expertise has been passed down over the generations. Forestry in Yoshino involves planting seedlings at densities of 10,000 trees per hectare (vs. 3,000 to 4,000 trees/hectare in customary forestry practice). The woods are subsequently improved by removing trees that aren’t growing well. This thinning is repeated several times based on the growth of the trees. Called “multiple thinning,” this process results in outstanding wide-trunked trees characterized by relatively uniform thickness from trunk to tip, few knots, dense growth rings, and straight wood grain.

In most places, final harvesting of trees that remain after thinning takes place after 40 to 50 years. At Yoshino, the trees are harvested after a much longer period of 80 to 100 years. Some trees are allowed to grow for 100 years or longer, depending on their condition. Because of this, Yoshino has maintained numerous thick-trunked trees that are 100 to 200 years old to this day.

Developing a 78-kilometer road network over roughly 30 years

I began working in forestry around 1980, when it was common practice to transport lumber that was harvested in Yoshino by helicopter. It was still profitable despite the expense for helicopter transport because the price of domestic lumber was high back then. However, lumber use for building interiors and exteriors began to decline from that time onward, as did demand for Japanese-style rooms and homes. The availability of low-priced, high-quality imported lumber also began in to increase. As I watched these trends, I worried that Yoshino lumber might become too expensive to sell, regardless of its quality.

That’s when I first suggested the idea of building forestry roads to Yoshino. I’d learned about forestry roads while studying forestry. My first attempts to build a road with my younger brother ended in failure due to a large-scale landslide. Since the mountains of Yoshino all have steep slopes, the sides of the mountains will collapse if we are not careful while building roads. One reason helicopter use was so common was that the numerous steep slopes made it too difficult to build roads for forestry. That’s when I met Keisaburo Ohashi, who had experience building high-density forestry road networks. When I saw the roads he was building, I felt they would be ideally suited to Yoshino. I became his apprentice immediately. We gave building roads another try. Since then, we’ve gradually completed a 78-kilometer network of roads on land we own. This took us about 30 years to accomplish.

Using roads to lower costs and improve working conditions

Building high-density roads suited to the terrain of my forests made it possible to transport thick logs from steep slopes using two-ton trucks instead of helicopters, which had long been considered the only practical way to get the timber out. The cost of transportation is about one-fourth that of helicopters. These roads also improved conditions for our workers by making it possible for them to access the mountains freely and safely. Extending these roads and making further improvements will enable us to respond to an increasingly diverse range of needs—for example, we could harvest and transport a single tree selected in the forest to fit a customer’s requirements.

I think it is now my turn to pass on the advantages of the road building methods I learned from Mr. Ohashi. Lately I’ve been giving lectures, training people, and providing hands-on experience for people who have expressed an interest in building forestry road networks. If even one of them actually begins building roads like I did when I was young, others who see them will start trying it themselves. I hope our approach will help protect the forests of Japan as this ripple effect spreads, making forestry healthier not just in Yoshino, but across the country.

Thinning holds the key to forestry’s future

Japanese government policies to expand forestation after World War II led to a rapid increase in artificially planted forests of cedar and cypress, which had high economic value. However, the forests are not maintained today because it would not be profitable to harvest them with the price of lumber so low, and some forests have consequently reverted to an unmanaged state. This means that the quality of the trees that grow there is not very high, and the terrain is more susceptible to mudslides in typhoons and heavy rains, which could have a negative impact on local ecosystems. If profitability is the only concern, a single-use forestry road could be built to clear-cut forests and harvest a large amount of timber at one time. But that would leave no trees to harvest over the next 15 to 20 years and could also damage the mountain’s ecosystem.

Using timber harvesting by thinning trees is one way to solve this problem. If timber from thinning were profitable, it could cover the cost of caring for the forests. This would ultimately make it possible to harvest high-quality timber. I hear that some areas and local governments have already begun promoting the use of timber from thinning. They are using it for buildings and furniture, and are developing the technology to use wood chips in biomass power generation. Competition with imported lumber is still likely to remain a factor, but I think there’s a pressing need for the Japanese forestry industry as a whole to broadly communicate the need to thin forests and the importance of developing new uses for timber from thinning, despite this.


While chatting with Mr. Okahashi after the interview, there was something I definitely wanted to ask. “What made it possible for the Okahashi family to continue owning the forests for more than 300 years, over 17 generations?” Surely there must be some reason you have been able to overcome so many challenges over the years. Mr. Okahashi sat up straight and looked into the distance as he answered. “Our predecessors often spoke about the importance of our core business. That’s why I’ve worked so hard to protect it. The most important reason, of course, is the love and care that our forest maintenance workers have shown for the forests of Yoshino.” His words, backed by long experience, conveyed the pride of one who has grown up alongside the forests of Yoshino.

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