Tree farming

Andrew and Suzi Sprigg of Wialki are planting their agriculturally unproductive soils to tree crops. They are passionate about the role tree crops can have in making their farm and their community more sustainable.

In Western Australia lies an area twice the size of Tasmania, called the Avon Wheatbelt. Of the 12 million hectares of land, approximately 8 million have been cleared. This extensive clearing has lead to environmental problems including wind and water erosion, salinity, and loss of habitat.

Agriculture is the predominant industry for this region but with narrowing margins and a changing climate, many who live in the region are looking for other options to be able to keep farming while still looking after the environment.

Industry scale planting of tree crops not only addresses these environmental issues but will provide sufficient resources for new industries. This will result in income diversification for farmers and increase local job opportunities.

This video is of 5 Avon farming families telling their stories -- about how they are trying to heal the land while developing new and sustainable production systems for their future -- their children's future and the future of their communities.

Thank you to Wheatbelt NRM for their vision for the health and sustainability of the Avon Region and for their sponsorship of this production.

**************************************

 The Oil Mallee Association (OMA) website; the mallee portal - the place for information, news and analysis on the oil mallee industry. The founders of the OMA can be justifiably proud with the creation of a new direction for agriculture and for its export to the rest of Australia.  OMA believe that this WA innovation is as important as the no till farming phenomenon, which started in WA and has now spread across the nation.

The OMA is dedicated to the extension of mallees as a landscape scale NRM tool for delivery of environmental services to help manage excessive water in the landscape and the potential spread of salinity, reducing the impact of wind erosion and providing an additional source of income for farmers through active management of carbon sequestration and bioenergy programs.

The branding of this movement as "oil mallee" comes from the intensive domestication of the different species of mallee eucalypts and their categorisation as being suitable for different uses in different regions. The research and development over many years has resulted in significant gains in vigour (growth) and in cineole (the core ingredient in eucalyptus oil). The level of cineole is important for eucalyptus oil production but also as a deterrent to grazing while in the early stages of growth.

Mallee is the common name given to a multi-stemmed tree.

They characteristically have many stems shooting out from an underground root mass just below the soil surface, known as the lignotuber or "mallee root" (a prized source of firewood). The lignotuber is an underground stem and believed to be an adaptation to fire. During fire or harvest, the above ground mallee stems are lost, but the starch rich lignotuber remains intact underground. The Mallee is able to sprout back from buds on the surface of the lignotuber, enabling the tree to survive. This process is known as coppicing.

Oil Mallees have the potential to generate tree crop revenue every 4-5 years once established. Moisture supplies mainly determine Mallee biomass yield and frequency of harvest. Eastern States experience indicates mallees may be harvested regularly for 100 years or more with no negative effects. In fact, as the lignotuber gets bigger, the coppice could be more robust and frequency of harvest could increase.

OMA and CALM (Dept. of Conservation and Land Management, WA) recognised in the early 90's that it was going to be difficult to ensure the profitability of oil mallees if eucalyptus oil was the only source of revenue. At present China can supply all the eucalyptus oil the world needs, so farming for eucalyptptus oil, alone, is not a viable enterprise. Consequently over several years, various other products derived from oil mallees were assessed. This led to the concept of integrated production and use of oil mallee products.

The Oil Mallee Association, Western Power Corporation, Enecon and CALM investigated an Integrated Wood Processing (IWP) system where oil, charcoal, activated carbon, and electricity are all produced in a combined process. The IWP plant at Narrogin has produced electricity, charcoal, activated carbon, and eucalyptus oil, from mallee feedstock grown on farms in the Wheatbelt of Western Australia.

 

Potential IWP sites

 

EcoGeneration — July/August 2008

When farmers in Western Australia’s wheatbelt started using oil mallee trees to control salinity, they weren’t aware of the massive potential crops’ to provide an almost unlimited supply of clean electricity to the state.

At anticipated rates of establishment, there is potentially more energy to be derived from oil mallee biomass than the energy in the amount of coal currently used to supply a large proportion of the Western Australia’s energy needs.

Adrian Chegwidden, sustainable energy business development manager of Verve Energy, which adapted technology to generate electricity from the trees, says the mallee represented an almost unlimited supply of energy biomass. This is a situation almost unique to Western Australia, which may have a major impact on the state’s future energy mix.

Pilot plant study demonstrates substantial potential
In 2000, a feasibility study into the bioenergy potential of oil mallees was commissioned by the Oil Mallee Company (OMC) in conjunction with Western Power and Enecon. The study identified that all of the mallee biomass (wood and leaf) could successfully be utilised in a processing plant to deliver energy, activated charcoal and oil and also found that the process was likely to be financially viable.

Following the study, a 1 kilowatt (kW) Integrated Wood Processing (IWP) demonstration plant was completed in Narrogin in 2006. The pilot plant successfully demonstrated the capacity for renewable electricity generation, charcoaling and carbon activation technology. The technology, developed by the Commonwealth Scientific and Industrial Research Organisation and adapted by Verve Energy, demonstrated that multiple-product processing systems appear viable.

Bright prospects for mallee bioenergy