A review on the effects of donor maturation on rooting and field performance of conifer cuttings

Synopsis The maturation and ageing effects of parent or donor plants have been reported to have both positive and negative influences on the performance of rooted cuttings. A general decline in rooting ability, root quality and speed of rooting in the nursery, and a reduction in tree survival, growth and form in the field, have been associated with donor plants that have reached a state of reproductive or ontogenetic maturity. Increased maturation has also been shown to affect wood quality negatively. Provided that donor plants are still relatively young, positive effects from increased donor age have been observed through an improvement in tree form and branching habit, as well as a reduction in bark thickness and stem taper. These improvements have resulted in increased timber yields over seedlings of the same genetic origin. This report summarises current understanding of the effects of donor maturation