Using Plugs and Hydrogels to Establish Populations of Prairie Dropseed, a Critical Native Grass, in Restored Prairies in Minnesota

Abstract

Prairie dropseed [Sporobolus heterolepis (A. Gray) A. Gray] is a critical North American native grass that is often not incorporated into prairie restoration seed mixes due to its low survival and growth rates. This project investigated using hydrogels, landscape plugs, and native field soil to improve the survival and growth of prairie dropseed. At three tallgrass prairie restoration sites at the Minnesota Landscape Arboretum, we planted prairie dropseed plugs in Fall 2019, Spring 2020, and Fall 2020. When grown in the field from 42 to 94 weeks, we found that potting mix–grown plugs had increased growth as measured by dry weight compared with plugs grown in native soils. Soil medium did not influence survival rates. The use of hydrogels did not demonstrate increased survival or growth compared with plugs planted with water. We recommend land managers and restorationists use plugs grown in commercial potting mix rather than grown in native soils, and we found no advantage in using hydrogels over watering at planting.