The short term effects of a fire fighting foam and fire retardant on selected flora from Australia's Southwest

Chemical fire suppressants arc used extensively throughout Australia's Southwest to contain and suppress wildfires. Despite several studies being conducted into their effects on terrestrial vegetation in North America and Eastern Australia, where a variety of significant effects were found, no such investigation has been carried out in Australia's Southwest. This study examined the short-term effects of a fire fighting foam and fire retardant on selected flora from Australia's Southwest. Various concentrations of fire fighting foam and fire retardant were applied to seeds and seedlings of several native species. Native species were chosen for their high abundance and widespread distribution throughout Australia's Southwest. Seed germination was assessed over 28 days for the number of germinants, whilst the seedlings were assessed on numerous growth characteristics over a ten-week period. Both the fire fighting foam and fire retardant treatments significantly reduced the germination of all seven species. Greater concentrations resulted in reduced seed germination. Both the 3.0% foam and 3.0% fire retardant treatments showed no sign of germination within the study period. The effect of the fire fighting foam on some native seedlings was significant, yet significant differences were inconsistent throughout the species examined and the variables applied. The fire retardant was far more influential on the growth characteristics measured and significantly affected all seven species. Significant responses included increases and decreases in biomass and improved and reduced plant health. From these results. it was determined that the use of fire retardants to control and suppress wildfires should be avoided where possible. The use of fire fighting foams between 0.1% and 0.4% foam concentrate is recommended as an ecologically sound and effective fire suppressant tool.