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APTTMI is a non-profit organization formed in 1997 in Iwate Prefecture.
Located in the northern mainland of Japan, Iwate was traditionally a farming, forestry and fishery area. However, since the 1960s the prefecture has developed manufacturing and technology industries, and many of its rural areas have become urbanized. Although the new industry has generally raised the income and living standard of the people of Iwate, it has also resulted in the loss of farming and other traditional industries. Young people have been leaving the rural communities, and traditional social systems have been abandoned for so-called westernization. 

A serious consequence of this social change in Iwate Prefecture is the disappearance of traditional buildings such as thatched-roofed houses, and the social system that helped support their maintenance and repair. A symbol of the local culture and landscape, these distinctive buildings are dependent upon a supply of kaya or thatch for their roofs, skilled professional thatchers, and a system of mutual help among neighbors.

To help preserve Iwate's thatched-roof houses, several concerned residents of Iwate Prefecture gathered and formed a non-profit association. The association's goal is to establish a model system to supply kaya (mountain reed) and train and secure professional thatching workers within Iwate Prefecture. 

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Representative: Yutaka Yoshioka
 Policy Advisor to Iwate Agricultural Junior College
 Chairman of Japan International Agricultural Council
Deputy Representative: Tadasuke Toda
 Livestock and Pasture Consultant
Secretaries: Kimio and Kyoko Segawa
 Director of Tohkohsha Co. and his wife
 Sakae Hinosugi, Former Master of Thatching Technique
 Osamu Segawa, Curator, Iwate Prefectural Museum
 Yohko Sugiwaka, Housewife
 Sumiko Yoshioka, Housewife
 Koichiro Ishikawa, Mechanical Operator
 iroshi Oyama, Mechanical Operator
 Masahiro Nagasawa, Assistant, Iwate Bio-research
 Kazuo Kamata, Former land engineer
 Hiroaki Shimo, Former Extension Official
 Yoshio Chiba, Former Agricultural Extension Agent
Address of the Office:
The Association for the Preservation of
Traditional Thatching Methods in Iwate (APTTMI)
c/o Kimio Segawa, 3-20-8 Higashi-Matsuzono,
Morioka City, Iwate Prefecture, Japan 020-0106
Tel/Fax: 81-19-661-4095

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Importance of preserving traditional thatched roof houses in Iwate and Japan
Preservation of traditional thatching methods is important not only for sentimental reasons or nostalgia for old things, but also to promote the value of the thatched roof house in the 21st century. Thatched roof houses provide a living space that is comfortable, pleasing to live in and environmentally friendly. At the same time these houses, symbols of Iwate's traditional culture and landscape, can be focal points for rural community revitalization and promotion of green tourism. 

Until several decades ago, you could see thatched roof houses almost everywhere in Japan. Rural communities of thatched roof houses, such as Nanbu-Magariyas in the Iwate area of the Tohoku Region, were recognized as symbols of Japan's beautiful landscape. The impression of this rural landscape was very gentle, and influenced the Japanese people to keep their minds in peace.

In these houses families lived, Kagura or traditional religious dances were performed, and wedding and funeral ceremonies were held. This traditional local culture and way of life had been handed down for many generations.

However, the number of traditional thatched roof houses in Iwate has decreased rapidly, reaching a critical level. If the current trend continues, they will almost totally disappear from the landscape in the next decade. 

Traditional thatched roof houses are unique buildings. Built with only local timbers and other natural resources, they are a good example of sound environmental construction. In the past, maintenance of these houses has been carried out through the traditional mutual relief system of rural communities. However, the traditional system in rural communities has collapsed and disappeared, and to replace it we need a modern mutual relief system covering the whole territory of Iwate Prefecture. 

The task of preserving the traditional thatched roofed houses of Iwate is difficult but very important. As John R. Moss, a Englishman who is aware of our activities in Iwate, said,

"Future generations will be the poorer and will condemn you if you fail."

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A video-tape produced to record the process of thatching in Iwate

As a first step, our Association has produced a videotape that documents the complete thatching process and the various techniques used to produce a traditional Iwate thatched roof. Mr. Sakae Hinosugi, the last thatching professional in northern Iwate Prefecture, and his assistant, appear in this videotape and demonstrate their superior thatching techniques. Soon after they completed this project, they retired from thatching work because of their age and health conditions. Therefore, the video has become the permanent record of their long contribution to the preservation of the local traditional cultural assets of Iwate. 

From the original long tape that documented the entire process of thatching, we have produced summary videotapes in VHS format, in both Japanese and English, to educate the public on the importance of preservation of traditional thatching methods and traditional thatched roof houses in Iwate. Copies of the video have been distributed to museums, institutions and individuals who are interested in traditional thatching methods. 

Copies of the video are available upon request for nonprofit use. We can also send copies of either version of the video, for the cost of producing and mailing the copy. To order a copy of the video, please send your request by email from the website or by fax to the office. We will respond to you with directions for ordering.

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Traditional methods of getting kaya (mountain reed for thatching) and a new modern method 

Thatching materials in Japan

In Europe, reed is commonly used as a thatching material. In Japan, reed (Yoshi) is also used for thatching in some areas. Yoshi is less perishable so it is considered a better thatching material than Susuki or mountain reed. However, yoshi is the most expensive thatching material, and because it only grows along the shores of rivers or lakes, it is not widely available. Sometimes yoshi is used in combination with other materials, to protect the roof from decomposition. Kaya or mountain reed is widely used as a thatching material instead of yoshi, since it grows in most areas of Japan. Some other local products such as Shima-gaya (grown on the shores of lakes or rivers), barley straw and rice straw are also used as supplemental materials for thatching. Most of the products belong to the rice family. 

Management of Kayaba (mountain reed growing ground)

In Iwate thatched roofs are made with kaya, which is grown naturally on uncultivated fields, or Kayaba, in rural villages.

The kayaba was traditionally uncultivated land owned commonly by community residents. In the early spring of every year, people burned dead leaves and brush on the kayaba to protect it from weeds and bad pests and to grow good quality kaya. We call this burning practice Hiire (fire introduction). Today, we rarely see burning kayaba since the demand for kaya has diminished and local fire controls have become very strict. 

In recent years, the APTTMI has successfully developed a method to clean three kayaba totaling 10 hectares, using radio- controlled tractors and shredders pulled by large tractors. In the spring of 2002, we expect to harvest 10,000 bundles of kaya (a bundle is approximately 25 cm in diameter at the base and 150 cm long) from our developed kayaba in central and southern Iwate. It is clear that the new production method can grow good quality kaya which can compete with that grown on kayaba managed with hiire. 

Harvesting Kaya 

Traditionally in Iwate, kaya is cut every year in late autumn, before the snow falls. The kaya is bound and left standing in the field. A bundle of cut kaya and a Shima (or Shime as it is pronounced in the Morioka area), which is formed with several bundles, are the volume units of kaya. Harvested kaya remains in the kayaba during the winter, and bundles of kaya dried under the snow are carried down after the snow has melted. 

Transportation and storage of kaya by individual residents and mutual relief systems for thatching

In the spring, kaya is removed from the kayaba and shipped to the thatching site, where it is stored under the thatched roofs of individual houses, in storage huts or on the open land covered with a tarp. In the past, the thatching of roofs was supported by community residents in a cooperative way. It was the custom for a family to harvest kaya every year on the kayaba commonly owned by their community, store their harvested kaya individually and return the same volume of kaya and labor to their neighbors as they had received from them in the past, when their roof was re-thatched with the kaya and the labor supplied by neighbors.

Experimental methods of harvesting Kaya conducted by the APTTMI 

In the autumn of 2001, APTTMI conducted a new, experimental method of harvesting Kaya in Iwate, which is quite different from the traditional one. This new method is aimed at overcoming current social problems in rural villages where there is a shortage of labor. We call the new method "the Niigata model," because it is based on a common practice in Niigata Prefecture, a district of heavy snows located on the Japan Sea side of the central mainland of Japan. 

In this new method, standing kaya was cut down before the first snow fall between early November and mid- December, 2001. The kaya remains on the ground under the snow until the snow melts in mid- April, 2002. At that time, the kaya on the ground will be naturally dried, bound and shipped to the storehouse.

If this harvesting method is successful, we can save a great deal of harvesting labor in late autumn, as compared to the traditional Iwate method. Moreover, most of the leaves of kaya can be expected to drop from the stems in the spring so that the quality and market price of kaya would be higher. 

Traditionally, small sickles are used to cut standing kaya to the ground. We have not yet found any other cutting tools or methods to compete with sickles in terms of labor efficiency. We will continue to experiment with machines and other tools to harvest kaya more efficiently. 

Favorable seasons for thatching the roof

When the Tohryo, or thatching professionals, see that the weather looks fine, the work of thatching is started. Thatchers try to avoid the rainy season (from the middle of June through the middle of July in most areas of Japan) and the farming season, since many of the thatching workers are part-time farmers. Extremely hot and cold seasons are also avoided since the labor conditions are too harsh. Therefore, the most favorable months for thatching are late April, May, early June, late July and September through November. 

Professional thatching workers

A thatching crew usually consists of the tohryo who plans and directs the whole thatching job, one or two Fuku-tohryo or assistant tohryo and several supporting workers. In the past, when the work was done with community mutual relief systems, many helpers from families in the neighborhood joined in the work.

In the past several decades, as the number of thatched roof houses decreased substantially, the number of professional thatching workers also decreased. In several areas in Japan, the few active professional thatching workers remaining are now very old. If all of the old thatching workers retire without any active successors, Japan's traditional thatching techniques will totally disappear. Therefore, along with a stable supply of kaya, securing future thatching professionals will be crucial to preserving thatched roof traditional houses in Iwate and Japan. Under the current social and economic conditions in Japan, we need to establish a institutional system to educate and train a certain number of younger people who wish to succeed those elderly thatching professionals. 

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Traditional thatching process

Ashiba-gumi or forming a scaffold of logs to support the thatching work

At the thatching site, a large scaffold of long logs is built for the work of thatching. The log scaffold is designed to make the thatching work easy and convenient. (See photo)

Tools used for thatching

After building the scaffold, the work starts. Many tools are used for thatching to meet the different conditions of each stage of the work. (See photo) 

Tools used for thatching are: 

Koshi Nata - a handy axe or hatchet
Satte - to flatten the edge of the kaya inserted into the roof 
Hasami - scissors used to trim the edges of kaya
Hari - a long, thin wooden or steel rod with a small hole at the end to pull a straw rope through the thatched roof 
Sashi-hera - a wooden tool to flatten the edge of Kaya
Mizu-nawa - a thin fabric rope used to make a straight line for cutting along the edge of the roof
Hera- to smooth the surface of the thatch
Ashikake - special tool developed by Mr. Hinosugi for supporting the feet of the thatching worker on the roof, where the scaffold does not reach
Kumade -a bamboo rake 
Oshikiri - a tool to cut kaya 
(See photos)

Process of thatching 

(1) Yagumi: The thatching work proceeds in an established order. The first stage is Yagumi. Long logs called Hokezao are placed upright and fixed with straw ropes to horizontal log beams called Zyoya. Each locality has its own traditional method for binding the logs with the rope. 

(2) Tomari-shiba: About 30cm below the top of the roof, the center point for thatching is marked by binding the Munagi (a long log) with Shiba, a rope made from a local plant. This step is called Tomari-shiba

(3) Ogaratsuke: After the framing logs are set, Sunoko, a screen made of reeds, is spread on top of them, and thereupon Asagara, or dried stems of Asa, is fastened with Osae-shiba. However, reeds are now used for this stage since cultivation of asa or hemp is prohibited.

(4) Nokizuke: The thatching work starts from the four corners of the roof. After kaya is fixed in each of the four corners, thatching workers move up, thatching along the line of the roof. Workers under the roof supply bundles of kaya to the thatching workers above, fastening them to Hokezaos.

(5) Tsukinarashi: Upon completion of thatching one side of the roof, a tool called Satte is used to make the edge of the thatched kaya straight and flat. This process is called Tsukinarashi. 

(6) Nijyo: After Tsukinarashi, a small roof is attached onto the main roof. This small roof is called Nijyo. Nijyo is attached with a long straw rope. Shorter stems of kaya are used to make this part.

In the places of the roof where the ashiba frame (or scaffold) can not be used, the Ashikake, a special tool invented by Mr. Hinosugi, is used. The tool has made the work much easier. Thus, the special talent of individual thatching professionals has added some new techniques to the traditional thatching methods and helped to develop the tradition.

(7) Hakomine: On the nijyo a wooden Hakomine is fixed with iron wires.

(8) Cutting extra kaya edges and making the roof flat: After thatching is completed, the surface of all sides of the roof is made flat by cutting the extra edges of kaya with Hasami or scissors from the top down. Then the roof is tapped with the Hera to make the whole roof smooth.

(9) Nokigari: The final process of thatching is Nokigari. Over the Nogi, or edges of the thatched roof, the Mizunawa or a straw rope is tied from one edge to the other. The Tohryo starts cutting the roof edge along the mizunawa to the middle of the roof, then he cuts the other half of the roof straight by cutting from other edge to the middle. 

(10) Now the whole process of thatching is over.

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Current activities of the Association

As we mentioned earlier, the major barriers to maintaining traditional thatched roofs, which are crucial to preserving traditional houses, have been (1) securing kaya for thatch at a reasonable price; and (2) the lack of thatching professionals. Therefore, the APTTMI has been working to develop modern systems to overcome these barriers. 

According to information we have received from various sources nationwide, it is clear that thatching professionals only remain in kaya-producing areas. Therefore, as a first step, the association began a project to develop model kayaba in three areas of Iwate prefecture: Tonan in central Iwate and Rokuhara and Kanegasaki in southern Iwate. We expect to harvest about ten thousand bundles of kaya in the spring of 2002. 

To achieve the above-mentioned goals of the association we have been and will be developing various programs including:

1) Production of a video to record the Iwate traditional thatching methods, in Japanese and English versions. Copies of the video are loaned or sent to applicants by mail for a fixed fee. Please contact with our office via telephone, fax or email. 

2) Research activities to locate appropriate kaya growing sites by using satellite data and field surveys in Iwate Prefecture.

3) Developing modern methods to prepare kayaba or kaya growing grounds by using radio-controlled tractors and shredders pulled by tractors instead of Noyaki or the traditional field burning, which is strictly controlled by fire stations. 

4) Experiments to develop labor-saving harvesting methods for supplying good quality Kaya. 

5) Survey on how to set an Iwate standard for a bundle of kaya for commercial distribution.

6) Public information activities to collect and propagate relevant information on existence of thatched houses, remodeling of old houses for better living, supplying kaya, the availability of thatching workers and volunteer helpers, establishing systems for training younger people to become thatching professionals and so forth. 

7) Developing a network of owners of traditional thatched houses through which information on the demand for kaya can be collected, and opening a consulting office to advise on how to secure needed kaya and thatching workers. 

Address of the Association for the Preservation of Traditional Thatching Methods in Iwate (APTTMI)
President: Yutaka Yoshioka E-mail:
Vice President: Tadasuke Toda
Office: c/o Kimio Segawa, 3-20-8 Higashi-Matsuzono, Morioka City, Iwate Prefecture 020-0106
Telephone/Fax: 019-661-4095
E-mail: HERE URL:

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"The first version of the English text was produced with the cooperation of Keiko Hentell (deceased), Education Consultant, in Los Angeles and the second and current version was produced with the cooperation of Mary Humstone, .Fulbright Senior Research Fellow"