National Arboretum Canberra Sampling Framework

During the first audit of the trees at the Arboretum in 2014, data on the trees used in the Growth Monitoring Project were incorporated in the maps supplied to the newly developing Arboretum geographic data base system. As a result, the Arboretum has formally adopted the sampling framework of the Growth Monitoring Project.

The sampling framework, based on a rigorous statistical sampling strategy devised by Dr Ross Cunningham, Centre for Research on Environment and Society, Australian National University, identifies a form of stratified random sample of each Forest that allows for three levels of variation in Forest performance to be assessed:

  • whole of forest,
  • potential variation due to local topography, and
  • genetic variation between trees within the Forest

This framework has the capacity to be used by other researchers for a diversity of purposes. Examples include, among others, phenological monitoring to track potential climate-induced changes or studies of other biota that utilise the forest for food, sources of prey or shelter (e.g. invertebrates, fungi, viruses).

Utilising the same trees as the growth study provides access to information about the growth history of each of the trees that can strengthen the power of other studies in understanding the particular focus of their research. Similarly, the use of the same trees for different studies opens possibilities for interactions between different studies based on the same trees.

To ensure the long term access to the sampling framework, including protecting the sample trees from untoward damage or removal from planned horticultural treatments within forests or future developments, the Arboretum has adopted advice from the Research Coordination Committee, that:

  1. The Arboretum formally recognises that the trees forming the basis of the sampling framework are of scientific significance to the Arboretum and as such are given special protection, but not special horticultural treatment;
  2. The trees that form the basis of the sampling framework will be identified within the newly developing geographic data base of the NAC, ensuring that all who access the maps of forests can see which trees form the sampling framework;
  3. The geographic database be regularly updated as the framework trees need augmenting due to losses of trees (this especially continues to happen during the early life of the forest trees).