OutdoorNebraska

Restoring the Blowout Penstemon with Bison Grazing T he blowout penstemon (Penstemon haydenii ) is a rare plant that grows only in blowouts in the western Sandhills of Nebraska and a dune field in the mountains in Wyoming. Blowouts are open, sandy wind-excavated depressions, mainly found on the dune tops. A short-lived perennial, blowout penstemon has sweetly fragrant, blue to lavender or pink flowers that bloom from late May through June. The plant can reach 2 feet in height and has waxy greenish-blue leaves. In the early 1900s, botanists described blowout penstemon as common in the Sandhills. Over the last century, however, it has declined in abundances as wildfires and natural disturbance by large herds of bison, which promoted the formation of blowouts, declined in the region. Today, only a few thousand plants still exist in Nebraska and Wyoming. Blowout penstemon was listed as a federal and state endangered species in 1987. In the 1980s, ecologists began efforts to restore populations of the penstemon in blowouts. At the time, a study concluded that it was ineffective to directly seed the plant in blowouts as the thick seed coat limited germination. Because of this study, over the last few decades, all blowout penstemon restoration efforts have used greenhouse-grown seedlings. The problem with using seedlings for restorations is that they can be costly to grow and have a rather low survival rate when transplanted into the wild. But even more problematic with past restorations was that without disturbance from heavy grazing or fire, over time, the blowouts commonly healed over with prairie grasses and the penstemons disappeared (the plants are poor competitors and can grow only in open sand). A few years ago, Greg Wright, a biologist with the U.S. Forest Service, got creative and began experimenting with planting blowout penstemon seeds in blowouts at Halsey and McKelvie National Forests in the Sandhills. He found that by spreading the seed in early winter in wind-exposed parts of blowouts, the sand, moved by brisk winter winds, scarified the seed coats and allowed seeds to germinate. His discovery greatly simplified blowout penstemon restoration. Another breakthrough in penstemon restoration came in 2017, when I was talking with managers of a bison ranch in the Sandhills and they were convinced that bison grazing would be more effective than cattle grazing to create blowouts. Bison are tough animals and spend significant time grazing high on dunes whereas cattle prefer the low ground. The conservation-minded ranchers also expressed interest in restoring penstemons on their ranch. Starting in 2017, and working with the Nebraska Game and Parks Commission and other conservation groups, they confined bison to a 200-acre pasture for long periods (with supplemental feed) to short graze the grass cover. In less than a year, blowouts started to form. In March 2019, we spread a pound of blowout penstemon seed into larger blowouts in the pasture and seedlings appeared that same summer. In coming years, the pasture will be heavily grazed periodically to maintain open blowouts. Additional blowout restorations in bison pastures may be the key to saving the penstemon. ✔ 3 Bison grazing is an effective method of creating habitat for growth of the endangered blowout penstemon. By Gerry Steinauer, Nebraska Game and Parks Commission Botanist PHOTO BY NEBRASKALAND MAGAZINE

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