Snow gums are experiencing dieback in Kosciuszko National Park, largely because of the impacts of the native longicorn (or ‘longhorn’) beetle. These beetles prefer to lay their eggs on moisture-stressed trees and, in warmer weather, the longicorn beetle can hatch and grow up to 75% faster. It is understood that climate change is helping the spread of dieback because of background warming.
Now spread of dieback is being seen more frequently in the mountain forests of Victoria. Gillian Anderson reports back on some recent observations of snow gum dieback on the Bogong High Plains.
On a recent 3 day trip to Falls Creek, my partner and I spent most of our time hiking around the southern end of the Bogong High Plains in the Alpine National Park. It was typical early January weather, relatively warm for the Alps with storm clouds building every afternoon… great walking conditions with expansive views (no smoke), and an absolutely stunning display of wildflowers.
In fact I can’t remember ever seeing the flowers quite so colourful and abundant; maybe it was the late spring / early summer storms, the light, or maybe just the perfect time for herbaceous flowering. No doubt the removal of cattle grazing after the 2003 alpine fires have helped all the alpine peatlands and herbfields recover!
Unfortunately what was not so great was at many locations the amount of snow gum dieback (and often death of the complete tree) due, we think, to longicorn beetle damage. This was especially disturbing to see in the huge old snow gums at Wallace Hut and Tawonga Huts. Many of these trees would be centuries old having escaped fires and surviving harsh winter storms for many decades.
I have recorded the sites and photos from our trip but as yet have not had the cause of the dieback confirmed, although the damage we saw looked very similar to the images on the Save Our Snow-gum web site.
Let’s hope the beetle damage is temporary (although obviously too late for many snow gums) or something can be done to save the ones remaining, as after the devastating alpine fires of recent years there are so few intact stands of snow gums left, especially the really old ones! These iconic snow gums may need some expert advice about potential treatments or intervention to help them survive.
It would be a great shame to lose them now…although if we don’t slow or halt the climate crisis the snow gums may only be one part of a ‘mountain’ of loss.
Gill has had a long career (over 30 years) in national park management, particularly in the Australian Alps. After leaving Parks Victoria Gill started a small protected area consultancy people in naturewhich she runs with her partner Peter Jacobs. Now semi-retired Gill spends as much time as possible walking in mountains (anywhere) and working with the IUCN World Commission for Protected Areas Mountain Specialist Group. If interested please go to: IUCN WCPA Mountains