Based on Shizuoka's Oi River, the Matsumoto family practices a centuries old way of farming called Chagusaba. Designated as a UNESCO Globally Important Agricultural Heritage System, the Chagusaba farming method involves surrounding your tea fields with fields of susuki or sasa, two different types of tall grass. In Autumn, the grass is harvested by hand, dried, chopped and laid on the ground around and between the hedges of tea fields providing soil fertilization, preventing the growth of weeds.
This system was studied and honored with the UNESCO designation because it has helped to preserve biodiversity in the areas of Shizuoka where it is widely practiced. Endangered insect species native to the region are also more widely found in areas practicing Chagusaba.