Traditional pergola system (Tana = frame, framework) in Japan, which has been used in wine and table grape cultivation since at least the 17th century. In the Japanese wine-growing areas there is high humidity due to frequent rainfall in summer. The shoots are led like a roof up to ten metres in all directions and overman-high on support wires. In winter, they are protected with straw mats. The large distance from the soil moisture reduces the risk of fungal diseases. The autochthonous grape variety Koshu is mainly cultivated in this way:
The picture shows a very old Koshu vine from Grace Winery (Yamanashi on the main island of Honshu). It has a trunk circumference of one metre. The shoots shown far away cover an area of 50 square metres. See also complete lists of relevant keywords on the topic at vine training (systems) and vineyard maintenance (activities).
Tanazukuri: By Sophie Jacquin - Own work, CC BY-SA 3.0, Link
Koshu grapes: By genta_hgr - Grape, CC BY 2.0, Link
old vine© Matthias Neske - Chez Matze
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