Post-fire recruitment and resprouting of a threatened montane eucalypt

Abstract

Changing climate is predicted to result in increased frequency and size of wildfires in south-eastern Australia. With increasing area burnt there is increased potential for entire species distributions to be burnt in a single fire event. This is particularly the case for range-restricted threatened species. Eucalyptus canobolensis (L.A.S.Johnson & K.D.Hill) J.T.Hunter is restricted to Mount Canobolas, New South Wales, Australia. In 2018, the majority of the E. canobolensis population was burnt by wildfire. One-year post-fire, we measured recruitment, resprouting and mortality of E. canobolensis. At higher fire severities, smaller trees were more likely to resprout from their bases only, as their stems were killed (i.e. ‘top kill’). Seedling regeneration only occurred in burnt plots. Our study demonstrates that E. canobolensis has a fire response typical of many eucalypts, characterised by seedling recruitment and larger trees resprouting epicormically, even after high-severity fire. Nevertheless, E. canobolensis response to repeat and short-interval fire remains unknown, and smaller trees appear to be vulnerable to top kill. Although much of Australia’s flora can respond to fire, this response is likely to be challenged as fire extents increase, especially if this is combined with increasing fire severity and/or frequency. These changes to the fire regime are a particular threat to species with restricted distributions.

Fire severity and the post‐fire soil environment affect seedling regeneration success of the threatened Persoonia hirsuta (Proteaceae)

“…Fire severity is projected to further increase under climate change in eastern Australia, posing a significant threat to the recovery of fire-sensitive native plant species (Williams et al 2009;Nolan et al 2021;van Oldenborgh et al 2021). Importantly, threatened species that are reliant on seedling establishment post-fire for persistence may be significantly impacted by changes to this aspect of fire regime (Bowman et al 2014;Zimmer et al 2021). In this study, we observed no apparent relationship among fire severity and post-fire seedling recruitment and growth in our study species.…”

“…2014; Zimmer et al . 2021). In this study, we observed no apparent relationship among fire severity and post‐fire seedling recruitment and growth in our study species.…”