A recent study has yielded valuable insights into the most effective silvicultural regimes for African mahogany (Khaya senegalensis) plantations in Australia’s north. The research will help maximise plantation productivity and wood quality, and help build confidence amongst lucrative new markets.
The study focussed on the Douglas Daly region of the Northern Territory, where commercial plantations were first established in 2006. Today, the total estate sits at around 14,000 hectares.
Researchers studied the impacts of thinning, fertilisation, pruning, and water supply on the growth and health of plantations, and on the processing properties of the resulting mahogany timber. The implementation of such practices was generally found to have a positive impact on plantation productivity.
Dr John McGrath, Principle of McGrath Forestry Services, who led the FWPA-supported research said African mahogany is an internationally important, high-value species, and early trials in northern Australia have demonstrated significant potential for plantation expansion.
“Previously there had only been limited investigations into the impact of management practices on the productivity and properties of African mahogany,” McGrath said.
“Understanding how fertilisation and management of plantation density impacts on wood quality, was identified as a significant knowledge gap in optimising the value of the plantations,” he said.
“By identifying what we need to do to maximise the value of the African mahogany from existing and future plantations in northern Australia, we can help growers obtain the best possible future commercial and environmental outcomes.”
The researchers used fertiliser trials, and soil and leaf nutrient assessments to help refine the relationships between nutrient status and growth rates. Thinning regimes were also assessed. In the majority of cases, optimising silvicultural inputs was found to result in marked productivity gains. The full findings will be made available via the publication of a report upon the project’s completion later in 2020.
These learnings will also be useful for a wider range of sites across northern Australia. Indeed, an analysis of critical climatic parameters identified extensive areas of land suitable for African mahogany plantations, not only in the Northern Territory, but also across northern Western Australia and Queensland.
The researchers and industry partners hope the outcomes will help to provide sustainable plantation management systems and the confidence needed to market Australian-grown African mahogany into valuable Asian furniture markets.
Funding for the project came from the Australian Government, and industry partners African Mahogany Australia (AMA) and Huntley Management.