Eucalyptus Vegetative Regeneration = Lignotuber + Trunk buds
Or how Eucalyptus nitens can coppice
Gustavo Iglesias Trabado 
GIT Forestry Consulting - Consultoría y Servicios de Ingeniería Agroforestal - www.git-forestry.com - EUCALYPTOLOGICS
GIT Forestry Consulting - Consultoría y Servicios de Ingeniería Agroforestal - www.git-forestry.com - EUCALYPTOLOGICS
Natural regeneration from dormant buds in the lignotuber and/or axils of old branches is one of the very interesting characteristics of many Eucalyptus species, having also very important implications for their cultivation and management as horticultural or timber crop.
Thinking forestry, for some Eucalyptus species it allows successive timber harvest cycles using the same tree stock, hence reducing the operating costs of repeated re-plantings after each harvest as it happens (for instance) with most conifers. It also allows reasonable chances of survival after fire, something almost impossible with other commercial species.
Thinking about a garden, it allows regular operations of size control involving removal of the aerial part with good chances of obtaining a multistemmed shrubby eucalypt in a relatively short period of time.
What happens when there is no lignotuber?
Fig. 1: Example of coppice growth in Eucalyptus nitens, traditionally considered a not very reliable coppicing species. New growth results from an undamaged axillary dormant bud placed near the collar of a discarded basal branch. No lignotuber is present. (Click to enlarge)However, several important and commonly cultivated eucalypt species, among them E. nitens, do very rarely develop a lignotuber and are traditionally quoted in specialised and non specialised literature as "non coppicing species". The pictures above can prove this is not always true.
Regeneration from basal axillary buds is very possible for this species. Also for other species not normally forming lignotubers. Now the importance of this fact does not reside in it being possible or not, but it being or not being frequent enough as to allow deciding if a productive stand of shining gum trees (or equivalent) should or should not be managed by coppice. Or if one of these trees planted in a small sized garden and needing removal due to excessive size, leaning or damage concerns can be expected to regrow.
There are several key factors to be considered for each of these cases, but the answers tend to be "it normally should not" for the former and "maybe" for the later.
Regeneration from basal axillary buds is very possible for this species. Also for other species not normally forming lignotubers. Now the importance of this fact does not reside in it being possible or not, but it being or not being frequent enough as to allow deciding if a productive stand of shining gum trees (or equivalent) should or should not be managed by coppice. Or if one of these trees planted in a small sized garden and needing removal due to excessive size, leaning or damage concerns can be expected to regrow.
There are several key factors to be considered for each of these cases, but the answers tend to be "it normally should not" for the former and "maybe" for the later.
Further Reading
- Little K.M., Van den Berg G., Fuller G. (2002) Coppicing potential of Eucalyptus nitens: results from a field survey. Southern African Forestry Journal 193, 31-38
- Oliver G.R. (1991) Growth and biomass of a Eucalyptus nitens coppice trial in New Zealand. In Menzies et. al. eds. Proceedings of IUFRO Symposium Efficiency of Stand Establishment Operations. FRI Rotorua, New Zealand, 11-15 September 1989. Pp 261-268
- Whittock S.P., Apiolaza L.A., Kelly C.M., Potts B.M. (2003) Genetic control of coppice and lignotuber development in Eucalyptus globulus. Australian Journal of Botany 51, 57–67
GIT's Eucalyptology Topics
© 2007 Gustavo Iglesias Trabado. Please contact us if you want to use all or part of this text and photography elsewhere. We like to share, but we do not like rudeness.
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