The Right Seed in the Right Place at the Right Time

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North American native plant seed is a valuable commodity and one that is in short supply. Current production may not always meet the growing demand, which is primarily for restoration of degraded landscapes. In response to this shortage, a strong and diverse coalition of federal and other agencies, as well as nonprofit organizations and private sector businesses, has developed the ambitious National Seed Strategy. The mission of the strategy is to ensure the availability of genetically appropriate seed reserves to restore viable, productive plant communities and sustainable ecosystems. Seed production in natural ecosystems ensures the regeneration of locally adapted plant species, which provide habitat for wildlife, stabilize soils, control surface-water flow, and contribute to ecological integrity and resilience. The United States has a native flora of over 18,000 species. In the western states, which have more diverse ecosystems and higher levels of plant endemism, there are around 14,600 native plant taxa. A recent assessment identified only 1949 of these as commercially available for use in restoration, the majority of species being sold by only one producer (White et al. 2015). This affects the restoration potential for degraded natural areas affected by human or natural events. Efforts to diversify and scale up native seed production depend to a large extent on adequate and reliable funding for development and ultimately on the market. Federal agencies are major buyers of native seed for land rehabilitation and restoration. The Bureau of Land Management (BLM), the largest federal land manager, alone purchases an average of 1.4 million kilograms of seed per year and often needs much more. The US government has been aware of the critical shortage of native plant materials for over a decade. The extensive wildfires of 1999 and 2000 led Congress to direct the BLM and the United States Forest Service (USFS) to develop a stable and economical supply of native plant materials for restoration and rehabilitation efforts on public lands (http://io.aibs.org/106914). The BLM and USFS responded by establishing the Native Plant Materials Development Program and the Native Plant Restoration Program, respectively. The immediate focus was to increase the availability of diverse native plant materials and to foster more efficient management of that supply. The two programs, mandated at the turn of the century, have achieved considerable success, but action needs to be scaled up to address growing ecological challenges. The causes of land degradation in the western states are now exacerbated by climate change. The resulting impacts on native plant populations and communities present urgent land-management challenges. The National Fish, Wildlife, and Plants Climate Adaptation Strategy, mandated by Congress in 2009, recognizes that “management plans in this new era of climate change must take into account the differing capacities of individual species and ecosystems to adapt to changing conditions and sustain cultural, recreational, and commercial uses.” Prolonged drought is a significant threat throughout the Southwest, with wildfires increasing in regularity and intensity. A related threat is the spread of invasive and noxious weeds. The natural resilience of heavily grazed native grassland ecosystems has been weakened by the use of introduced grass species initially intended to stabilize soils and improve productivity. Modified grasslands can be rapidly colonized by pernicious introduced species brought in by the movement of people, their crops, garden plants, and livestock. Efforts to restore the land involve both tackling invasive species and restoring native plants. In the rangelands and steppes of the Great Basin and inland Pacific Northwest, cheatgrass (Bromus tectorum), an invasive species introduced from Europe in the 1880s, is spreading fast. Cheatgrass-dominated land burns every 2–5 years. Land rich in sagebrush and other native species, in contrast, is more ecologically resilient, burning every 11–200 years (Koch et al. 2015). In January 2015, an order by the secretary of the Department of the Interior called for enhanced action to prevent and suppress rangeland fire and to restore extensive fire-damaged sagebrush communities. The order specifically calls for the utilization of locally adapted seeds and native plant materials for vegetation management and restoration. It therefore provides a powerful supporting motivation for the National Seed Strategy. Generally, the plant species used in a restoration project vary according to the vegetation type, land use, extent of degradation, availability of material, and established practices. Restoration projects often focus on the use of dominant plant species because these are more widely available and are considered to be more important for ecosystem functioning. The importance of using native material, the importance of genetic provenance, and the use of cultivars are still widely debated, however. Before 2000, grasses, predominantly nonnative ones, have dominated restoration use. On the Colorado Plateau, for example, nonnative crested wheatgrass has been planted extensively to enhance livestock grazing after the removal of pinyon–juniper woodland. Although it is commonly held that introduced species perform better than natives, this view is based more on philosophical preference than on data (Wood et al. 2015). Likewise, the notion that the use of cultivars of native species selected for vigor, seed production, disease resistance, and habit is highly advantageous—not least because cultivar seeds are widely available and easy to sow using seed drills—is common. However, cultivars, with their limited or altered genetic variation, may have poor ability to adapt to climate change. National policy directives call for the use of native plant species in restoration to the extent practicable. To address this imperative, a change in cultural attitudes will be required—specifically, a shift away from agronomic toward ecological restoration models. Science alone may not convince all practitioners, but demonstrating restoration success, adaptive management, effective communication, and public support will strengthen the case for using native, locally adapted seeds. Unfortunately, native plants do not have the charisma they deserve, but flagship animal species can help make a strong case for restoring biodiverse, plant-rich ecosystems. In the West, the greater sage grouse (Centrocercus urophasianus), a species heavily dependent on sagebrush landscapes, is one such species. Currently being considered for listing under the Endangered Species Act, the bird has declined dramatically over the past 100 years because of habitat loss. The BLM is making major efforts to restore sagebrush habitats on its land. In the East, the bobwhite quail (Colinus virginianus) is another game bird that is attracting widespread concern. The National Bobwhite Conservation Initiative, developed by 25 state wildlife agencies, with many conservation and research partners, is restoring native grassland habitats and healthy populations of wild quail. So what are the National Seed Strategy's chances of success? The initial signs are promising: a high-level policy framework, background initiatives that the strategy will build upon, and a strong coalition of support. The National Seed Strategy will, for example, build on the work of Seeds of Success, a national native seed–­collection program led by the BLM. In the past 15 years, Seeds of Success has made more than 16,500 seed ­collections representing over 5000 taxa (Haidet and Olwell 2015). Collecting seed from native species is the first stage in developing a reliable commercial source, which takes on average 10–20 years per species. In parallel, germination and propagation protocols have been developed for over 3000 species. Furthermore, over 120 native species have been made commercially available, and foundation seed for over 70 additional species has been provided to commercial growers. Two US Department of Agriculture facilities provide long-term seed storage. The four interrelated goals of the National Seed Strategy also bode well: to identify seed needs and ensure the reliable availability of genetically appropriate seed; to identify research needs and conduct research to provide genetically appropriate seed and to improve technology for seed production and ecological restoration; to develop tools that enable managers to make timely, informed seeding decisions for ecological restoration; and to develop strategies for internal and external communication. With the launch of the National Seed Strategy, federal agencies with responsibility for managing nearly 30 percent of the US landmass will work together to facilitate native seed production from diverse native plants. A business plan is currently being developed that will highlight opportunities for the private sector to become more involved in supporting the strategy. Nongovernmental organizations are on board. Scientific, technical, and cultural challenges remain, but the National Seed Strategy will represent a quiet but profound revolution in land management.