FOBIF has just received the Box-Ironbark Experimental Mosaic Burning Project_Newsletter 5, on research conducted in the Heathcote-Rushworth forest. The newsletter documents important features of forest structure, like the presence of large trees, and the quality of ground cover. It’s a brief and interesting document. Its interest lies, however, in what it doesn’t say, rather than what it does.
The newsletter points out something we all know: that box ironbark forests are highly modified by past practices, and that ‘important structural features’ like large trees, and deep leaf litter are ‘exceedingly rare.’ The research documents this in painstaking detail.
So: it’s ‘important to know how planned burns may further alter forest structure, and what effect they may have on already limited forest resources.’ Work is under way to ‘compare pre and post fire data’ , and the results will be detailed in future newsletters.
We can’t offer comments on the forests over at Heathcote-Graytown, but here are a few comments on the matters raised by the Project:
–Almost every prescribed burn we’ve examined in our area has destroyed some of the ‘exceedingly rare’ large trees in the relevant zone.
–Deep leaf litter is a problem: for ecologists it’s an important feature of forest health. For fire managers, it’s just fuel.
The moral of this seems to be that fuel reduction burns are definitely bad for forest structure, unless they’re done in very small patches, with painstaking attention to detail [impossible under the present regime, where managers are compelled to burn large areas to get up to the five per cent].
One further point: the researchers might want to compare their findings with past Departmental burn plans. These are supposed to record the effects of prescribed burns on the very things the researchers are looking at [see page 40 of the 2006 Code of Practice, for example. The 1995 Code is a bit vaguer, it also requires monitoring and research into particular burns]. They might find this material hard to find, however: we’ve never succeeded in getting access to it.
Much overlooked is the effect of frequent fire on the leaf litter biota, particularly invertebrate species. The absence of such specialised biota contributes to the big litter problems in Spanish and other plantations