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Kosuge Village, the town of water sources

What is Kosuge Village?

Kosuge Village, located at the headwaters of the Tama River deep in the mountains, has a population of 700 people and 95% of the land is forest. Despite the shrinking population, this village is characterized by its beautiful scenery, bounty of forests, and clean water. In fact, many people living in Tokyo regularly see spring water flowing from Kosuge Village in the Tamagawa River and elsewhere, and the village is deeply connected to our daily lives.

Yamame farm

Due to this rich water source, Kosuge Village can be said to be a town that lives in harmony with the water source, with specialties such as wasabi, which can be said to be the cornerstone of Japanese cuisine, and the river fish yamame (yamame trout). Kosuge Village, which is surrounded by mountains 360 degrees, is about two hours from Tokyo, and in recent years, regional revitalization efforts have been active in response to microtourism and relocation to the suburbs due to the coronavirus. Specifically, there are decentralized hotels like Nipponia, and various initiatives such as turning entire towns into hotels are attracting attention. This time, we will take a look at the charm of Kosuge Village, focusing on the topography unique to its water source and the food that comes from it.

Water source and wasabi

Photo by DAIWA HP

Wasabi has been growing wild in the rich nature of Kosuge Village since ancient times, and it is said that cultivation began around the middle of the Edo period. Wasabi grown naturally in clear streams gushing out from the valley has a rich flavor and firm spiciness, and is well-received for its high quality. The important things in wasabi cultivation are water temperature (8~9℃) and water volume, and the headwaters of Kosuge Village are said to be optimal for both. Kosuge Village, blessed with its topography, boasts one of the highest levels of wasabi cultivation in Yamanashi Prefecture. According to what I heard when I bought wasabi at a long-established wasabi shop in Okutama, wasabi is at its spiciest in the winter. In the summer, wasabi receives sunlight and grows larger, including its leaves, but in the winter, sunlight is limited to only the roots, and the small roots have a pungent taste. In addition, Kosuge Village uses a cultivation method called the Jizawa method, which can be developed even in areas with narrow streams and low water flow. This cultivation method is unique to Kosuge Village, where water can be directly drawn in from the stream, but the stone walls of the stream break during heavy rains, making it difficult to grow delicious wasabi. I understand.

Water sources and fish farming

Kosuge Village, which is rich in nature, is also famous for its yamame (yamame trout) farming area. Kosuge Village is the first private village in Japan to successfully hatch yamame trout artificially. There are two reasons why the fish farming industry became popular after the artificial hatching of yamame trout. This means that the water is clean and the amount of water is appropriate. If there is too much water in the river, there is a risk of fish being washed away, so the amount of water that is unique to the water source is suitable. Just like wasabi, the cleanliness of the water and the appropriate amount of water are also useful for yamame trout farming. The Kosuge fish farm we visited is located along a river, and by forming it into contour lines without going against the topography, it has become a beautiful building that blends in with the village landscape. I think each village is a wonderful village, with its own topographical characteristics as well as its own industries and lifestyles.

Geography and local culture

The background of food culture is greatly influenced by the geography of the area. Geography influences local crafts, architecture, and towns, and can be said to be the source of the things and things that surround us. Although we now live in an age where we can enjoy things and things anywhere, we believe that there are hints to enriching our lives by learning about Japan's ancient aesthetic sensibilities and ways of living. In addition to disseminating information about towns, architecture, crafts, and food that are connected to Japan's ancient aesthetic sensibilities, we also operate a select shop that focuses on handicrafts. If you are interested, please check the select shops as well.

OBORO Select Shop Link

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