Chicago Botanic Garden Spring 2019

Conserving our prairie, one seed at a time Medard and Elizabeth Welch Senior Director, Ecology and Conservation. It aims to preserve at least one representa- tive sample of each of the roughly 3,000 species found in the tallgrass prairie ecosystem that produce seeds capable of surviving cold storage and multiple samples of more than 500 species important for restoration. is is important work. roughout North America, the tallgrass prairie has lost nearly all its former distribution to agricultural and other human activi- ties. Seeds in the bank are being used for research and plant conservation ef- forts that are protecting rare plants from extinction and restoring habitats, including degraded Forest Preserves of Cook County sites, with resilient prai- rie species. Here is a closer look at this valuable resource. Why does the Garden have a seed bank? First, many of the represented plants are rare, and it’s important to store seeds to prevent their extinction. For example, many of our native ashes were hit hard by the emerald ash borer. We’ve been collecting genetically di- verse samples of ash species in the hope we can preserve them before they die. If scientists and land managers nd a way to get emerald ash borer under control, we may be able to restore them or man- age a icted areas by propagating bor- er-resistant cultivars and providing seed stock for large-scale restorations. Ash is only one example. With wave after wave of new diseases and insect threats, many species are not currently rare but may be in the future. We need to have genetic material in the bank to restore plant communities after a blight or infestation. The Dixon National Tallgrass Prairie Seed Bank safeguards an endangered habitat From the outside, the Chicago Botanic Garden’s Dixon National Tallgrass Prairie Seed Bank resembles the freezer of a commercial kitchen, the sort of large, double-doored, stainless steel chamber you’d nd contestants racing toward on a Food Network competi- tion. But inside lies something far more consequential. On shelves lined with vacuum-sealed foil bags is a collection of physical seed specimens, stored at minus 18 degrees Celsius, that repre- sent species integral to the tallgrass prairie biome of the midwestern Unit- ed States, one of earth’s most endan- gered habitats. Most seed banks in the United States focus on preserving the seeds of crops and crop relatives, but the seed bank in the Daniel F. and Ada L. Rice Plant Conservation Science Center has a dif- ferent goal, says Kayri Havens, Ph.D., By the numbers 200 years: The potential storage time for each collection | 3,000 species: In the tallgrass prairie ecosystem that are suitable to be preserved | 15 percent: The level of humidity of the dried seeds