A general growth stage key for describing trees and woody plants

Abstract B iologishe B undesanstalt, Bundessortenamt and CH emical Industry (BBCH) scales are a system for the uniform coding of phenologically similar growth stages of plants, using a two‐digit decimal code. Currently, scales exist for a number of tree and woody species grown as crops; however, researchers are often forced to adapt existing scales or create their own when describing other tree or woody species growing as crops or weeds. This paper describes a general BBCH scale for the phenological growth stages of tree and woody species, including plant‐specific descriptions and decimal codes covering vegetative and reproductive stages. The scale uses eight of the 10 principal BBCH stages, starting with sprouting/bud development (stage 0) and ending with dormancy (stage 9). This BBCH scale represents a single, standardised growth stage key for describing the growth of needle‐bearing and leaf‐bearing woody plants and promotes the adoption of the use of BBCH scales more widely. It is expected that the scale will form the basis for the creation of further scales specific for family, genus or species.