See G. W. Adriance and F. R. Brison, Propagation of Horticultural Plants (2d ed. 1955); H. Hartmann and D. E. Kester, Plant Propagation (5th ed. 1990).
Cutting is the separation of a physical object, or a portion of a physical object, into two portions, through the application of an acutely directed force. An implement commonly used for cutting is the knife or in medical cases the scalpel. However, any sufficiently sharp object is capable of cutting if it has a hardness sufficiently larger than the object being cut, and if it is applied with sufficient force. Cutting also describes the action of a saw which removes material in the process of cutting.
Cutting is a compressive and shearing phenomenon, and occurs only when the total stress generated by the cutting implement exceeds the ultimate strength of the material of the object being cut. The simplest applicable equation is stress = force/area: The stress generated by a cutting implement is directly proportional to the force with which it is applied, and inversely proportional to the area of contact. Hence, the smaller the area (i.e., the sharper the cutting implement), the less force is needed to cut something.
When referring to propagating plants, cutting is one of the methods that can be used. It involves cutting a part of the plant typically a healthy shoot, with sharp and sterile scissors or any other cutting device, and then placing the removed part in water. Some cuttings do not require water. Certain shoots when cut are able to grow when placed in vermiculite or potting soil. However, the former is the easiest to do as most shoots when cut from the main plant need time to grow roots, and then they are able to be transferred to potting soil.