The prevalence of special-status plants within a landscape can be an indicator of the ecological health of that site, and therefore inform restoration efforts and post-restoration monitoring. Hesperevax sparsiflora var. brevifolia (short-leaved evax) is a special status species found within the Ocean Ranch unit of Humboldt, California. A primary threat to native plant communities are invasive plant species. Coastal dune ecosystems are largely dominated by invasive species, including Ammophila arenaria (European beachgrass). To work towards the eradication of A. arenaria, the California Department of Fish and Wildlife utilized treatment combinations of herbicide and prescribed fire at Ocean Ranch in the fall of 2022. We worked with the California Department of Fish and Wildlife (CDFW) to study the density and abundance of H. sparsiflora var. brevifolia, proximity to A. arenaria, soil compaction, and distance to the road within specified areas. We estimated a total of 14,354,293 H. sparsiflora var. brevifolia individuals in the polygons we measured. We found that the further from A. arenaria, the greater the likelihood of H. sparsiflora var. brevifolia individuals. However, our findings showed that the number of individuals and distance to the road was not a significant relationship, and the relationship between the number of individuals in burned versus unburned quadrats was not significant. This project can serve to monitor the establishment of special-status species to observe the success of recent restorative treatments and to guide future restoration.
Environmental Science & Management
Environmental Science and Management