The purpose of this observational study was twofold: to add to the existing data regarding the plant species composition of the Pepperdine hillsides and to set in place a foundation for post-fire chaparral recovery studies that will ensue over the coming years through various programs and classes. The 2018 Woolsey Fire burned nearly all of the natural environment surrounding Pepperdine University and the greater Malibu region, so it is a matter of urgency to take this opportunity to learn more about how this natural environment of the chaparral responds to a catastrophic event like fire. We focused primarily on facultative and obligate resprouters, hypothesizing that Malosma laurina would have increased in its relative density on the hillside, and that Ceanothus spinosus would have seen reductions in its relative density due to its physiological disadvantages compared to M. laurina. Using the study site located at the top of Baxter drive which was established in 1986, we conducted a Point-Quarter Sampling Analysis. At the Baxter study site there are 32 plots designated by stakes in the ground which divides the study site evenly and provides points of reference from which to analyze the composition of the chaparral stand. We found that, by a considerable margin, Malosma laurina was the most frequent species in the stand, making up over half of the shrub resprouts observed in the analysis. Comparing to 1986, it is clear that it has maintained its position as the dominant plant, having increased in its relative density at the study site by 22.2% (Figure 5b). Ceanothus spinosus did not see drastic reductions but had a lower relative density in 2019 by 7.08% (Figure 5b). Further studies will assess seedling success as well; the stage of ecological succession that the hillside was in upon initiation of this study hindered that analysis.
Stenz, Emma C.; Grinovich, Brandon R.; William, Catherine H.; Gayed, Michael E.; Davis, Stephen D.; and Palmer, Grace, "A Survey of Post-Fire Chaparral Species’ Densities Using Point Quarter Sampling" (2019). Pepperdine University, Featured Research. Paper 165.