Survey of Chicago Region Restoration Seed Source Policies

摘要

Where to obtain seed for new and ongoing restoration projects is a primary concern for land managers of the Chicago, IL region. Restoration practitioners here face a challenging situation. On one hand, many pre-settlement plant communities are still intact; Chicagoland boasts one of the Midwest's most significant concentrations of remnant biota(Chicago Wilderness 1999). On the other hand, increasing urban sprawl, altered fire regimes, climate change, and invasive species may be leading to the development of novel ecosystems and altered stable states that differ from any previous historical system(Cramer and Hobbs 2008, Nowacki and Abrams 2008). Transplant, common garden, and long-term in situ experiments have shown that plants are adapted to local environmental conditions(Linhart and Grant 1996)and that outbreeding depression is possible when locally adapted genotypes are crossed with those from more distant populations(Keller et al. 2000). Results from these experiments have created a general reluctance among field practitioners to use genotypes from beyond relatively small distances from the restoration site(McKay et al. 2005, but see Leverich and Schaal 2005). In some cases, restoration efforts have simply been abandoned because no local or affordable seeds were available(S. Packard, personal communication). However, completely abandoning potential projects may not be warranted, as using local seed may not always lead to the greatest performance of restored populations(Bischoff et al. 2010).