Professor / Veg Panel Executive Committee University of Northern Colorado, United States
Abstract: One of the major plant related restoration activities is the Seeds of Success (SOS) program initiated by the Bureau of Land Management (BLM) and various federal and non-federal partners in 2001. A general assumption in the National Seed Strategy and the SOS program is that locally collected seeds will perform best in habitat restoration because those seeds will contain locally adapted genotypes. This assumption is supported by considerable ecological and genetic research, but has not been widely tested in plant restoration studies. In this study we aim to test the hypothesis that ‘local’ seeds germinate and survive better than non-local seeds, which we tested in the sagebrush system of western Colorado.
Seeds of seven target species distributed throughout the intermountain basin geographic area were obtained from the Seeds of Success program from three spatial scales: 1) local – seeds within 100 km of the restoration site; 2) Regional – within 200-400 km of the restoration site; and 3) global – >400 km from the restoration site. Three sites were selected within the Sagebrush Steppe ecosystem near Kremmling, CO, USA. Experiment trails were organized into a randomized block design with five replicates at each site. Each block contained eight 2 x 2 m2 plots with one of eight treatments: A) control, no seeds added; B) local only seed; C) regional only seed; D) global only seed; E) mixed local and regional seed; F) mixed local and global seed; G) mixed regional and global seed; and H) mixed local, regional, and global seed. Both density of seedlings that emerged in plots as well as diversity were affected by the interaction of site and planting treatment.
In general, the Central site (which maintained the greatest soil moisture) had the most individuals and the greatest diversity, which was also generally true for planting treatments that included the ‘local’ accession. Control sites were clearly the lowest in density and diversity, suggesting differences in other treatments were partly due to planted accessions. When examined the seven target species, the interpretation was the same while the non-target taxa did not significantly differ among planting treatments, again suggesting planting treatment differences due to accessions planted. Local accessions had higher diversity, composition and survivorship. Plots with local seeds developed different communities than those with regional and especially global seeds, but this effect was less when examining only target species. Our data support the importance of local seeds in restoration.
