He had botanical knowledge, and according to legend when he was 103 years old he engaged in the improvement of grape cultivation (using an overhead trellis method for the vines) (source: 'Koshu')
本草学にも通じ、103歳の頃に甲斐におけるブドウ栽培法の改良（ぶどうの棚架け法）も行ったとする伝説もある（参考「甲州(葡萄)」）。