Rooting variables for stem cuttings

Variables describing rooting in stem cuttings are generally inadequately defined. When there is any mortality in the propagation nvironment, several variables, including the commonly used "number of cuttings rooted as a percentage of the original number", are composites of the initial survival of cuttings in the propagation environment and the rooting of survivors. These composite variables can be, and often are, confusing. The non-composite variables are: "the number of cuttings surviving the propagation phase as a proportion of the original number" (SurvP), "the number of cuttings rooted as a percentage of those surviving the propagation phase" (Rooted(%)SurvP), and "the number of roots per rooted cutting"(R/Rc). Their use makes it clear which elements of the propagation system are being evaluated, allows treatment differences to be distinguished reliably and prevents wider misconceptions from arising.