The industry’s concerns over root to shoot balance specifications in the Australian tree stock standard appear to be backed up by initial data being collected by researchers involved in the research project aimed at refining the standards to reflect real patterns of growth in live production systems.
The team from the Hawkesbury Institute of the Environment recently provided an update on progress to date to the steering committee, made up of grower and industry representatives.
The literature analysis phase of the project is exploring the implementation of similar standards in overseas countries, particularly Europe and the United States where there is extensive data on applying tree stock standards in field production settings.
The existing standards internationally are similar in many respects but differ in their implementation and in the range of tree species and types. They do, however, serve as a good comparison in informing the way that the project team proceeds with collecting data and applying it against quality standards.
The field survey phase started with visits to Alpine Nurseries at Dural.
The existing standard shows a simple exponential relationship between a tree’s size and its soil volume. However, the team is expecting significantly greater variation between a tree’s size index range (its trunk calliper compared to its height) and the container volume.
This very early concept will be tested as data is collected at field sites but is consistent with some of the initial observations being made at the field sites.
Other highlights presented to the meeting included:
- Appointment of the field researcher, former HIE student and now PhD graduate Dr Court Campany
- Follow-up and feedback from February 2016’s NGIA Conference where comments on the selection of tree species and regions was provided
- An outline of the proposed processes for visiting nurseries in each state to ensure valid measurements in the main climatic regions of Australia
- An outline of the processes involved in field site visits to ensure transparency, minimise disruption and adhere to an efficient flow in taking measurements.
- An updated list of tree species on the ‘target list’ and categorisation of tree types into workable groups for sampling purposes.
Project Code: NY15001