Managing Murray's mighty river red gums
River red gums are prolific seeders.
The management of our iconic Murray River and its surrounding forests is drawing increasing attention. Sarah Chester reports on Forests NSW role in the management of river red gum forests and wetlands in the region, and the beautiful and valuable timber products that result.
Forests NSW is responsible for managing more than 150 000 hectares of State forests along the Murray and Murrumbidgee River systems. This represents just a part of the 530 000 hectares of red gum forest in Victoria and New South Wales.
Gary Rodda, Forests NSW Riverina regional planning manager, said that in any given year about four per cent of the 110,000 hectares of river red gum available for harvest was selectively harvested.
“The red gum forests are sustainably managed for a range of social, economic, and environmental benefits that flow on to the community,” Gary said.
“The red gum industry in the region supports approximately 400 full-time jobs with huge flow-on effects.
“These are ‘working forests’, managed for a vast range of activities including timber production, beekeeping, fish harvesting, recreation, tourism, conservation, grazing and water management,” Gary said.
At around age 40, poorer quality, young red gums are harvested, mainly for firewood. The better trees benefit from reduced competition and grow to reach
their full potential.
“This harvesting process is carefully managed to ensure a patchwork of tree sizes and ages in the forest, which means there is a good selection of habitat for fauna and flora,” Gary said.
At around age 60, the first red gum sawlogs are selectively harvested, producing mainly smaller sawlogs used for landscaping and heavy construction. Any better quality logs are directed to furniture markets.
At around age 80, the red gums undergo their second harvest, which produces high quality sawlogs for products such as furniture, floorboards and veneer, as well as heavy structural timber.
The final harvest is carried out when the red gums have reached maturity at about age 90. This harvest ensures that the right conditions are created for regeneration to occur by removing small groups of trees (less than a hectare), to create enough light and space for seeds to germinate and thrive.
Forests NSW active forest management ensures that patches of trees of different ages are spread throughout the forest to maintain a diversity of habitats.
All harvesting is carried out in accordance with a harvest plan approved by NSW Department of Environment and Conservation. The plan has a range of conditions to ensure that flora, fauna and archaeological values are protected.
“This means that across the harvest area a proportion of trees are marked and retained for animal habitat, while other trees with the potential to develop hollows for animal habitat are also marked and kept,” Gary said.
River red gums are prolific seeders, but they only regenerate well where there is plenty of light and open space. Growth for the seeds lying on the forest floor is triggered by flood, fire, heavy rain or mechanical disturbance.
The forest ecosystems are characterised by their peculiar reliance on a winter/spring flooding period, followed by a summer/autumn drying phase to maintain their ecological diversity, health and vigour.
Forests NSW and water management agencies have been managing water for many years by using ‘regulators’ – gates along the forest rivers that can be opened and closed depending upon the season and allocation of ‘environmental flows’.
“Forests NSW management has helped sustain these magnificent and iconic forests and we are committed to ensuring the red gum forests flourish for future generations of Australians,” Gary said.
Following flooding, large numbers of waterbird species breed including the great egret, intermediate egret, nankeen night heron, carp-eating cormorants and locust-eating ibises. Photo by David Klenert
Wonderful wetlands
As the Murray River meanders through the red gum forests it forms wetlands – including swamps, marshes and lagoons.
Forests NSW management of these wetland ecosystems is very important to the ecology of the region as they form an integral part of the forest food chain.
In these quieter backwaters, giant rush, cumbungi grass, water milfoil and moira grass are often prolific, while the lagoons provide excellent habitat for native fish and birds.
Following flooding, large numbers of waterbird species breed including the great egret, intermediate egret, nankeen night heron, carp-eating cormorants and locust-eating ibises.
Another important part of Forests NSW management system is the work undertaken with Greening Australia to regenerate large areas of regionally significant sandhill and box woodland communities.
In May 2003, 84 000 hectares of State forests in the central Murray were added to the list of ‘internationally important wetlands’ under the Ramsar Convention.
The convention recognises the current sustainable management, which includes more than 100 years of timber production.
New South Wales is also participating in ‘The Living Murray’ initiative, managing the Millewa and Koondrook/Perricoota State Forests as ecological assets under this leading river restoration initiative.
Premier products
Red gum is a strong, durable, termite-resistant timber, making it ideal for landscaping, fencing and outdoor furniture.
The better quality timber is increasingly kiln-dried and converted into products like floorboards, furniture and veneer.
The proportion of appearance grade and structural timbers in the region’s sawlog production mix has gone from 25 per cent in 2001 to 58 per cent in 2005.
After sawlog harvesting there is usually a quantity of limbs and smaller branches left behind, suitable for collection as firewood. Care is taken to ensure that sufficient habitat is left for ground-dwelling native animals.
Firewood collection, like sawlog harvesting, is strictly controlled by Forests NSW staff who actively manage the conditions and areas in which it is allowed.
Forests NSW sells high quality, low quality and residue logs to a range of customers who have invested more than $5 million during the past five years in value-adding equipment and downstream processing technology.
Major red gum customers include Gulpa Sawmill at Deniliquin, Bonum Sawmill and O’Brien Sawmills at Barham and Arbuthnot Sawmills at Koondrook in Victoria.
The owner of Gulpa Sawmill, Ian Danckert, said the mill had recently purchased a drying kiln from Italy and was putting on more staff to cope with the growing demand for high quality red gum products.
“Our investment in value-adding technology is typical of a wave of industry development and investment in red gum across the region,” Ian said.
The managing director of Arbuthnot Sawmills, Paul Madden, said the red gum industry had created employment in the mid-Murray region for the past 140 years.
“This employment is critical to the economic and social sustainability of local towns,” Paul said.
“Every part of the red gum is utilised and marketed. Even the sawdust and bark is used in potting mixes and garden mulches, or as biofuels to generate energy.
“Apart from a strong furniture industry, red gum is important for infrastructure with the timber used for ports and wharves, bridges, railway sleepers, and even cladding the hulls of Murray River paddle steamers.
“The red gum timber industry and tourism complement each other. Tourism has been a part of the multiple-use management of the red gum forests during the past century.”
Paul said people should understand that timber produced from sustainably managed red gum forests was renewable, did not require any toxic chemical treatment and stored carbon for many decades.