Alpine Ash (Eucalyptus delegatensis) is the classic tree of the sub alpine forests and tends to be replaced by Snow Gum woodlands at higher elevations. In Victoria it is also known as Woolybutt. It only exists in south eastern Australia (there is also a sub species in Tasmania). In Victoria, it occurs at altitudes between 900 and 1,500 metres above sea level.
It has had 84% of it’s range in Victoria burnt since 2002. Large fires occurred in 2002/03 in the north of the Alps, in 2006/2007 in the south. And during 2019/20, around 83,000 hectares of Ash forest was burnt, with 17,800 hectares of this being reproductively immature ash forest that burned at high severity.
We know that large old trees in ecosystems in Victoria which are dominated by Alpine Ash are in ‘rapid decline’. The problem is that Alpine Ash need around 20 years to reach reproductive maturity, so if fires happen more frequently than this, local extinction is possible because there is no seed stock to create a new forest.
New research shows us, yet again, that increased fire regimes threaten this vegetation community. Future fire regimes increase risks to obligate-seeder forests by Sarah C McColl-Gausden, Lauren T Bennett, Dan A Ababei, Hamish G Clarke, and Trent D Penman, and published on 23 September 2021 describes the impacts of fire on Alpine Ash.
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