It refers to the main trunk in a group and is related to two or more trunks among bonsai trees. The name is given to one that is the thickest, tallest, most powerful and holds the core position in the entire group. Its other names are shingi (the highest tree in group planting) and shinkan (parental trunk). Whether shukan is good or bad has a major impact on a bonsai tree in determining whether bonsai is good or bad and also on its value as a plant for appreciation.

translated by Kyodo News