Our Remarkable Old Trees: Part 1
Greg Siepen, Daniel Cole and Jan Allen
VTGA - Veteran Tree Group Australia
When visiting forests or national parks, we often take for granted the large trees that we walk by or camp near. These big, old trees are remarkable, not only for their size, but also because they have many other important values, such as containing their own ‘ecosystem’, showing a slice of the region’s history, significance for Traditional Owners, exceptional age, rarity, important habitat or ecological associations, and having exceptional landscape values and great beauty.
As a group, they are affectionately referred to as veteran trees. They need conservation and management to ensure they live their full life, which may be several hundreds or thousands of years.
National parks, state forests and other protected areas are the ideal sites for conservation of these valuable trees. They can be left to contribute to the local ecosystems unhindered, be available for viewing by visitors, and not pose safety issues which can occur if they are located closer to human infrastructure.
In this article we will cover characteristics and values of veteran trees, their specific relationships, historical importance, and significance to Traditional Owners. In part two the survival and sustainable management strategies for veteran trees will be discussed.
Characteristics and values of veteran trees
Veteran trees reflect the longer, slower cycles of the natural environment, on which we depend for all the essentials of life. By virtue of their longevity, veteran trees provide an enduring, stable habitat structure that determines the long-term survival of any ecosystem. Veteran trees have the following values:
Ancient DNA: Very old trees may be over a thousand years old and composed of DNA material of forests that were present before Europeans settled Australia. They are the remnant survivors of the original forests and for survival need protection by law, whether located in national parks, on farms, or in council reserves.
Soil stabilization: Veteran trees, like all trees, have roots that bind the soil and reduce the potential for erosion, especially along waterways.
Prevention of salinization: All trees are great water pumps, not only pumping water from ground level to the highest leaves, but exerting pressure to keep water deep in the soil to prevent salinization.
Habitat: Veteran trees, like all trees, provide perches for raptors on which they can survey their kingdoms, find their prey, and clean up animal carcasses, acting as nature’s recyclers. Trees provide foliage for many invertebrates and bird species, offering protection from predators. The foliage also provides shade and shelter for other plant species during the hot summer months or during violent storms.
Many tree species also attract a great variety of pollinators that keep the forests healthy.
One specific benefit provided by veteran trees is the development of hollows. Hollows are essential for many species of Australian wildlife that play a beneficial role in keeping our forests and general landscape healthy. Researchers believe that it takes about 200 years for large hollows to develop in native eucalypt trees which are used by mammals such as greater gliders. Smaller gliders and tiny insectivorous bats will also shelter in any size hollow. It has been estimated that 95 species of mammal and approximately 50 bird species use hollows for shelter and nesting.
While having veteran, hollow-bearing trees living in forested national parks is beneficial, it is also very desirable to have these ancient trees living in agricultural and pastoral landscapes to provide habitats for beneficial pasture and crop destroying predators, such as insects, spiders, micro bats, and insect eating birds.
Species specific relationships & partnerships: Trees and other life forms have co-evolved over centuries in Australian forests. Hence, they have built up close beneficial partnerships. For example, as a tree ages it starts to break down with the help of fungi and invertebrates (wood borers). In some instances one fungus species may be restricted to only one tree species. Some insects are found only at the tops of certain trees in our ancient rainforests.
Historical importance and value to Traditional Owners
Historic importance: Veteran trees may be only a few hundred years old, but have witnessed European explorers traversing the continent, graziers and pastoralists opening up productive lands and new towns and cities growing up. Trees have played a vital role in all these activities.
Some veteran trees contain the slash marks of explorers or surveyors’ markers. Graziers and pastoralists often marked trees to identify their paddock boundary fence lines. Early settlers also removed bark for roofing shingles. Unfortunately, few veteran trees containing marks remain in and around cities due to the mindset of housing and industry developers of clearing all their land to start with a ‘clean slate’ – a trait that is still done today when new suburbs are developed.
Aboriginal significance: Cutting bark off trees for Aboriginal uses has declined since European settlement began and many Aboriginal scarred trees are now well over 100 years old and are becoming rare as they age, die or are removed.
Aborigines removed bark to make shelters, canoes and containers, identify culturally significant trees (e.g. carving), manufacture artefacts (e.g. shields, spears), collect food, and to assist in climbing trees.
Scarred trees can tell us a lot about the history and development of an area. Firstly, scarred trees are a timely record of Aboriginal traditional places and events. Secondly, scarred trees can tell us where canoes were manufactured, where groups of people lived, or from which trees they collected food (e.g. toe holds on trunks of ‘sugarbag’ trees). Finally, the characteristics of the scar can tell us whether stone or metal tools were used.
Summary: Veteran trees have many important values and play a significant role in their ecosystems. They help maintain environmental stability and complement other parts of the landscape which may have shorter life cycles. In part two we will investigate the survival strategies of veteran trees and how we can manage and protect them.
Veteran Tree Group Australia (VTGA) organises workshops and has expert information about veteran trees and their management. More info: www.facebook.com/Veteran-Tree-Group-Australia.