Assessing the Value of Potential “Native Winners” for Restoration of Cheatgrass-Invaded Habitat

Rebecca S. Barak, Jeremie B. Fant, Andrea T. Kramer, Krissa A. Skogen "Assessing the Value of Potential “Native Winners” for Restoration of Cheatgrass-Invaded Habitat," Western North American Naturalist, 75(1), 58-69, (1 May 2015)  https://doi.org/10.3398/064.075.0107 

 

Summary:

Cheatgrass is an invasive species that can degrade ecosystem diversity and function primarily due to its early germination (sprouting) period and its ability to outcompete native plants, especially in post-fire ecosystems where native vegetation is limited. Barak and colleagues conducted a study to determine which plant species are “native winners” against cheatgrass. “Native winners” are native plants that have suitable characteristics to persist in invaded habitats. For this study, seeds from 10 different native forb species were collected from across the Colorado Plateau region and tested for viability (ability to sprout) under different temperature conditions, simulating possible fall conditions when cheatgrass germinates. Then, the five plant species with the highest germination were used in a competition study with cheatgrass to assess their growth in a cheatgrass-invaded environment. Results showed that all five species were suppressed by cheatgrass, however, three species, Foothill Deervetch (Acmispon humistratus), Sand Dune Cat’s-Eye (Cryptantha fendleri), and Tanseyleaf Aster (Machaeranthera tanacetifolia), were suppressed the least. These species could be used for restoration in cheatgrass-invaded habitats, especially Foothill Deervetch and Tanseyleaf Aster because they provide additional ecosystem services, including nitrogen fixation and flowers for pollinators. 

 

Take-home Points:

  • Plant species used for restoration in cheatgrass-invaded ecosystems should have the ability to persist and compete with cheatgrass. 
  • Foothill Deervetch, Sand Dune Cat’s-Eye, and Tanseyleaf Aster were found to have the ability to persist in cheatgrass-invaded habitats due to their high seed viability and ability to compete with cheatgrass. 

 

Management Implications:

  • Seeds of the “native winners” could be produced commercially and used for widespread ecosystem restoration in post-fire and cheatgrass-invaded habitats. 
  • Out of the 10 species studied, only one (Penstemon palmeri) is commonly used in ecosystem restoration efforts, indicating strong potential for improved restoration outcomes through incorporation of these newly identified species. 
  • Using “native winners” for restoration could direct ecosystems towards trajectories that could be more resilient against fire and future invasions.