Cushion plants are candidates for alpine trail revegetation because of their adaptation to extreme environmental conditions, their ability to persist in disturbance, and their role in facilitating other plants. This 7-year study monitored cushion plant transplants used to revegetate a closed alpine trail on Mount Yale. We measured the success of using mature cushion plants as an alpine revegetation tool. We also assessed the population of cushion plants and the non-cushion plants they facilitated to better understand alpine succession after disturbance. Lastly, we tested the stress gradient hypothesis and evaluated cushion plants’ role in bringing higher species diversity to disturbed areas.
Results/Conclusions
The transplants lived until 2015, but all died by 2017. However, due to new recruitment from the nearby community, in the final monitoring year, the cushion plant population in the trail increased to 156% of its baseline population. In the final year, we assessed the diversity and abundance of cushion plants and the plants facilitated in their canopies. The most dominant cushion species was Minuartia rubella, followed by Minuartia obtusiloba. The most dominant, facilitated species was Festuca brachyphylla. Elevation (p=0.859), slope (p=0.703), and soil moisture (p=0.745) did not influence the composition and abundance of cushion plants recruited into the revegetated trail (NMDS ordination). However, the composition and abundance of their canopies’ plants were influenced by soil moisture (p=0.001) and elevation (p=0.005), weakly influenced by slope (p=0.052), and not influenced by size of cushion plant (p=0.347) (NMDS ordination). Findings suggest cushion plant recruitment is promising and not limited by elevation, slope, and soil moisture. This study also suggests that cushion plants facilitate plants with a range of different elevation, slope, and soil moisture preferences.