Revegetation of a Trampled Cliff-Edge Using Three-Toothed Cinquefoil and Poverty Grass: A Case Study at Tettegouche State Park, Minnesota

Abstract

Cliffs and cliff-edges are often attractive places to humans, and therefore may become damaged through recreational activities. Restoring cliffs and cliff-edges, which can be important sites of biodiversity, is challenging in part because of insufficient knowledge about native plant restoration techniques for these ecologically distinct areas. The cliff-edge at Shovel Point in Tettegouche State Park, Minnesota, has been damaged by heavy visitor use. We propagated 450 three-toothed cinquefoil (Potentilla tridentata) and 450 poverty grass (Danthonia spicata) plants from locally obtained seed to test revegetation techniques. We seeded plots with cinquefoil and poverty grass seeds for comparison with transplanted plots, we monitored survivorship and seedling recruitment for three seasons, and we counted the number of new shoots produced at 3 and 24 months after transplantation. Visitor access to planted areas was restricted during the study. Overall survival rates at 3, 13, and 24 months were 87.3%, 76.9%, and 68.9% for three-toothed cinquefoil and 98.7%, 96.7%, and 63.8% for poverty grass. The grand mean number of new shoots produced per plant was 0.37 and 2.11 (SE = 0.227, 0.365) at 3 and 24 months respectively for three-toothed cinquefoil and −0.21 and −3.15 (SE = 0.584, 0.295) at 3 and 24 months respectively for poverty grass. Only one seeded plot had a single poverty grass plant by the end of the study. One-way ANOVA tests revealed no statistically significant differences among treatments within species for survival or number of new shoots produced. We conclude that when transplanted, three-toothed cinquefoil and poverty grass are useful species for revegetation of damaged outcrops such as Shovel Point.