Case study of in situ seed harvesting in restored grasslands to increase native seed availability

Abstract

We used a Woodward Flail-Vac seed harvester to harvest slender wheatgrass (Elymus trachycaulus (Link) Gould ex Shinners [Poaceae]) from a restored grassland at Grand Teton National Park. Seed was harvested over 3 continuous d, covering an area of approximately 5.5 ha (13.6 ac). Total seed yield was 291 bulk kg (642 bulk lb) or equivalent to 53 bulk kg/ha (47 bulk lb/ac). Estimated hours of labor for 3 d of harvesting plus time processing at the Aberdeen Natural Resources Conservation Service Plant Materials Center totaled 120 h. When comparing the resources and environmental inputs required for in situ seed harvesting to the conventional native seed production, given an appropriate setting, in-field seed harvesting may offer a viable additional method to supplement the need for native seed. In addition, in situ harvesting may offer an effective, affordable, and environmentally sustainable alternative for procuring significant amounts of seed of locally adapted ecotypes for restoration plantings.