ARI research on the life-cycle of Banksia spinulosa var cunninghamii (Hairpin Banksia) is being used by fire managers to help maintain plant diversity in forests when applying fuel reduction burns.

This species typifies plants that decline if burnt too often, because they don’t resprout after fire, take a long time before producing seed, and have no soil seed banks. The interval between fires needs to be long enough for plants to mature and produce sufficient seed, and for enough seedlings to survive to replace the parent populations. It is important to determine the minimum time between fires needed to retain these types of species, as well as accounting for the effects of fire severity and rainfall on recruitment.

Seed production (number of cones per live adult plant) and seedling recruitment (number of seedlings per dead adult plant) in response to fire were studied at two Hairpin Banksia populations; just east of Melbourne, and in far east Gippsland. Results indicate that fire intervals of at least 15 years enable Hairpin Banksia populations to maintain an adequate seed source. Where fire intervals were lower than this, plants produced very little seed and populations may decline. Very low numbers of seedlings (~ one seedling per adult plant) were recorded at almost all sites. A small pilot study on whether fire severity would affect cone opening and subsequent seedling recruitment had inconclusive results.

Guidelines have been produced in collaboration with operational burn planners in DELWP and Parks Victoria. The guidelines are based on ARI’s research findings since 2014, in the context of hotter, drier weather conditions. These include: checking cone production prior to burning, varying burn intensity: patchiness within burns; and delaying burns in drought conditions.

Banksia cone

Banksia seedling

The findings on fire intervals for seed production are being applied in regional fire planning by DELWP and Parks Victoria to support Victorian Government fire policy. Funds and in-kind support were provided by DELWP's Forest, Fire and Regions Group, and Parks Victoria.

See the fact sheet below for an overview of the project and results:

For more information contact: annette.muir@delwp.vic.gov.au

Information on ecological evaluation of planning burning can be found on DELWP's Monitoring, evaluation and reporting page

Page last updated: 30/10/19