Koyo Bonsai Concave Cutters

Standard shears leave a flat cut that can create an unsightly bump as the tree heals. Concave cutters remove a small amount of wood around the branch base, creating a slight indentation that allows the tree's bark to grow over the wound flush with the trunk, resulting in a much cleaner, less visible scar.

Yes, but they are a specialized tool. While they are professional-grade, they are essential for anyone serious about bonsai because they prevent the long-term scarring that can ruin a tree's aesthetic. If you are working on trees with branches thicker than a pencil, this is a foundational tool you will eventually need.

At 10.75 inches long, these are designed for larger branches that standard shears cannot handle. While the exact capacity depends on the hardness of the wood, they are built to comfortably manage branches up to roughly 3/4 to 1 inch in diameter.

Keep the blades clean of sap and debris after every use by wiping them with a soft cloth and a light application of camellia oil. Avoid cutting wire or dead, hardened wood, as this can chip the precision-ground edges.

The bypass mechanism is critical for these cutters. It allows the two blades to slide past each other like scissors, which creates the clean, shearing action necessary to slice through live wood without crushing the branch tissue, ensuring the tree heals as quickly as possible.