Following up on Ferocious Focus: Trellis Systems, I will introduce the trellis system that Kusunoki Winery, a winery located in Suzaka, Nagano in Japan uses.
But before that, let’s discuss some of the environmental factors that Kusunoki Winery considered when choosing its trellis system. The main factors are fertile soil and wet weather, which together cause rapid vine growth, or high vigor.
According to the Kusunoki Winery website, the winery is located on an alluvial fan called the Hitakihara. An alluvial fan is a fan or cone shaped deposit of sediment built up by streams. It is typically composed of a mixture of clay, silt, sand and gravel. This mixture is fertile and provides good drainage. Major wine regions that benefit from an alluvial fan include Napa Valley in the United States, Stellenbosch in South Africa and Alsace in France.
The good drainage part is key for Kusunoki Winery, which receives higher amounts of rainfall than most wine growing regions. In fact, according to Jancis Robinson, Japan is generally unsuitable for viticulture because it has a monsoon-like climate that leaves excess water in the soil. This high rainfall coupled with fertile soil can cause vines to grow rapidly. Rapid growth, or high vigor, is generally not good because it causes the vine to spend more energy on growing shoots and leaves and less on producing grapes. It also causes the vine to grow too many leaves. These leaves shade the grapes and prevent proper ripening.
The Smart-Dyson Trellis System
Kusunoki Winery uses the Smart-Dyson trellis system to combat high vigor. The Smart-Dyson trellis system has one fruiting wire along which a cordon is trained with spurs pointing up and down (see photo above). These spurs will grow into vines. Some of these vines will grow upwards and some of will hang downwards. The “up and down” part is key as it:
- De-vigorates the vine: The Smart-Dyson trellis system helps slow growth, or de-vigorate, vines because it forces half of the vines to grow downward. Vines naturally grow upward so forcing a vine to grow downward causes it to be stressed and grow less.
- Increases canopy surface area: The Smart-Dyson trellis system increases canopy (the part of the vine with leaves) surface area (e.g., 60% more than vertical shoot positioning). It does this by spreading out the canopy upwards and downwards. This allows more leaf exposure and, therefore, more photosynthesis and better ripening.
- Decreases fungal disease: Wet weather perpetuates fungal diseases. The Smart-Dyson trellis system helps decrease fungal disease because it divides the canopy in half. This makes the canopy less dense and increases air circulation around the grapes.
Other wineries in Nagano such as Sun Sun Winery and Shinshu Takayama Winery also use the Smart-Dyson trellis system. It is another way that Japanese wineries are adapting and striving to make better grapes and wine.