FireFire

Fire

The summer of 2019–20 was the first opportunity since the discovery of the Wollemi Pine to study the response of wild individuals to fire (Mackenzie et al. 2021). Fire scars on the trunks of most mature adults at the time of the species’ discovery indicate that the groves have been impacted by, and survived, past wildfires (NSW DEC 2006a). The coppicing habit of the Wollemi Pine may have helped it survive previous fires as it allows for the development of new shoots to replace fire-killed trunks (Burrows et al. 2003).

Field surveys of the wild Wollemi Pine population after the 2019–20 bushfires revealed that most adult trees survived the fires with their upper canopies intact (Mackenzie et al. 2021). Of the fire-affected trees greater than or equal to 2m tall, two-thirds suffered partial canopy loss and one-third (predominantly juvenile trees) were completely top-killed (Mackenzie et al. unpubl. data). Of these top-killed individuals, approximately one-third were killed outright with the remainder (c. 20% of the post-fire population) reduced to vulnerable basal resprouts (Mackenzie et al. unpubl. data). The pre-fire bank of seedlings and smaller juveniles < 2m tall has been 92–95% eliminated with only 4–7% of pre-fire individuals successfully resprouting (Mackenzie et al. unpubl. data). However, this bank of smaller juveniles is expected to re-establish from seed over the next 20-30 years (Mackenzie et al. 2021).