Abstract The spread of buffel grass (Cenchrus ciliaris) in semi-arid Australia in recent decades has substantially
increased ground cover and fuel loads, particularly in open woodland vegetation communities. The resulting
alteration of fire regimes may be the most significant impact of buffel invasion on ecological communities in these
areas. Broad scale management of buffel grass is currently not an option in Australia but it is becoming increasingly
relevant to assess the benefits of restoring areas of native vegetation where preventing buffel grass invasion is
no-longer possible.We managed buffel grass in a series of experimental plots from 2008–2012. In June and August
2011, two unplanned fires burnt through the plots providing a unique opportunity to compare the outcome of
wildfire, including the spatial pattern of fire, and the effect on ground vegetation and on a long-lived, perennial
overstorey species, in replicated managed and unmanaged plots. The area of ground that remained unburnt was
much greater in managed plots (with predominantly native vegetation) than unmanaged (predominantly buffel
grass) plots and where the managed plots did burn the fire was more patchy. This had direct implications for the
richness of ground layer plant taxa following fire and the extent to which overstorey trees were exposed to fire. Fire
increased pre-existing differences in the number of taxa in the ground level vegetation, an effect that persisted for
the duration of our study, suggesting that fire accelerates direct negative competitive effects between buffel grass and
native grasses and forbs. Hakea divaricata (fork-leafed corkwood) trees in unmanaged buffel grass sites suffered
higher burn intensities, and their long-term viability at this location is likely to be threatened if fires fuelled by buffel
grass continue. Our results demonstrate clear benefits of removing fire-enhancing invasive plants from areas of high
conservation value.
Key words: buffel grass, Cenchrus ciliaris, fire, Hakea divaricata, invasive grass, restoration.
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