In early 2009 Treelogic was involved in a pilot study with the Australian Capital Territory (ACT) Government to undertake a tree inventory and make recommendations about future auditing needs so that the ACT Government can better manage their ageing tree assets through a renewal and cyclic maintenance program.
This could seem a straight forward task, but Canberra is a city full of trees. The ACT Government alone, on public land manages an estimated 630,000 trees, with 440,000 trees being in urban parks and streets. The enormity of these numbers starts to make the process more complex. The problem is further complicated by the short time periods in which many trees were planted. Canberra is not unique in this respect as tree planting in most cities and towns also coincides with land development activities.
To give an idea of the rapid tree planting that took place in Canberra, in the Parliamentary Triangle alone, under the direction of Thomas Weston, the First Superintendant of Parks, over one million trees were planted in nature strips and parkland in a 4 year period in the early 1920s.
Canberra has experienced three big population growth periods; firstly at the time of the city’s inception in the 1920s, the 1950s-1970s and in the current day. Trees in the first period were mainly exotic, and trees in the second period were mainly native. The native trees are proving to be more short lived than the exotics, and both are ageing, declining and becoming hazardous simultaneously.
Trees now dominate the city and provide many aesthetic and social benefits that the residents value. However as we know trees don’t live forever and the ACT Government has embarked on a strategic approach to renew the urban forest for future generations.
Changing weather patterns add to the challenge of identifying poorly performing species and selecting appropriate trees for replacement.
The ACT Government has identified 5 key drivers for its Urban Forest Renewal Program and they include:
- Decreasing the Government’s exposure to risk from tree related incidents
- Maintaining the ‘look and feel’ of Canberra
- Maximising the benefits of the urban forest
- Normalising the age-class structure
- Prepare for changes in climate
The ultimate aim of urban forest renewal activities is to analyse the entire public urban forest and design a program that identifies those streets and parks where renewal is a priority. The ACT Government has sought expert advice from leading heritage, planning, urban development, horticulture, landscape architecture, forest and climate change experts. It has been well recognised that communication will play an equally significant part in the success of the program and thus community engagement and involvement is also at the forefront in planning decisions.
The analysis of the public urban forest will utilise geographic information systems (GIS). This will enable tree managers to spatially and graphically understand the forest structure and condition. With an understanding of these attributes, tree managers can plan for the renewal of targeted sections of the urban forest.
Treelogic believes the approach adopted by the ACT Government is at the cutting edge of urban forest management in Australia and is proud to be involved with the early stages of the project.
October 6, 2009
Arboricultural management, Major Projects