Northern Prairie Wildlife Research Center
A few may know this, but most do not. The Sheyenne National Grassland offers the last best hope for restoration of tallgrass prairie in North Dakota.
And in a state indelibly linked to prairie lands, remarkably less than one tenth of one percent of all tallgrass prairie in North Dakota lies intact. Nationwide, just one percent remains. No other major ecosystem on the North American continent - not Pacific Northwest old-growth forest, not tundra, not Southwestern desert, not Eastern deciduous forest - has been so fully altered by people.
Located in southeastern North Dakota in Richland and Ransom counties, this 70,000-acre Sheyenne grassland straddles the ancient Sheyenne River Delta, where prehistoric meanderings of the river flowed into glacial Lake Agassiz - forerunner to the Red River Valley. Just a century ago, this area played host to native grasses, some as high as a man: big bluestem, switchgrass, Indian grass and prairie cordgrass.
But as settlers moved into the area, surrounding prairies surrendered to the plow, especially the rich black earth of the Red River Valley. However, because of its sandy soils, early farmers usually held back the plow from land in the Sheyenne River Delta. Now, the Sheyenne National Grassland is a prairie island, a biological oasis in an intensively cultivated region.
That's not to say the ancient delta is an unaltered throwback in time. The Sheyenne National Grassland has been significantly altered. As early as 1880, settlers drove livestock into the area. By the turn of the century, white-faced cattle grazing behind shimmering barbed wire fencelines were a familar sight.
|Fire helps to recycle nutrients and sets the stage for diverse, healthy plant growth. Controlled burns are used by range managers as a tool to revitalize prairie vegetation.|
While livestock grazing affected the land, its effects were less severe than plows and combines on surrounding farmlands. As a result, some grazed native prairies were spared the more damaging effects of busting sod.
Even so, some of the delta's grasslands were plowed under. Armed with imported strains of wheat, homesteading laws and the wet years prior to World War I, area farmers plowed ancient delta lands into production. But by 1935, searing heat and extended drought had already parched the words "dust bowl" to the lips of mid-continent Americans. Summer winds whipped sands into the fury of the jetstream, which carried fragile Great Plains soils thousands of miles east. In so doing, the winds hurled an urgent message to Washington, D.C. There, senators could literally look out their windows, watch the noon-day sky darken with dust, and say, "Good God! The Great Plains are blowing away, clear across the Atlantic!"
Since the days of the last glacier, about 25,000 years ago, the Sheyenne River Delta has had a fair number of sandy "blow-outs." In fact, many grassy hummocks typical of the area are all vegetated blow-outs. Blow-outs are created by wind. Once started, the wind picks at the blow-out, like a scab. In drought conditions, or when lands are grazed too intensively, blow-outs don't easily revegetate, and the land suffers greatly.
The drought of the '30s coupled with cultivation were hard on the land. As dry weather wore on, cultivated lands lost their ability to retain vegetation. Hot air dried soils, which the wind picked up and blasted in tremendous dust storms across the continent. Through the stripping of plant life by heat and the shearing away of the soils by wind, the Sheyenne River Delta was dressed in more and more blow-outs, creating far too many highly eroded sand dunes. The land fell into obvious disrepair. As America slipped deeper into the Great Depression, a stupifying knowledge took hold. Prairie lands had to be respected. Historic drought cycles had to be anticipated. Antiquated farming practices had to give way to more modern concepts of resource sustainability and soil conservation. Industrialized agriculture had to comply, at least in part, to the dictates of weather, water regimes, and a whole host of other ecological considerations.
|June grass doesn't grow as tall as a man, but it is common in the Sheyenne Deltas.|
Arising from the dust bowl was a growing appreciation for worthwhile innovations: contour plowing, livestock rotation, and a shelterbelt tree-planting program to block wind from blowing soils away.
Finally, in 1937 Congress responded to the message so forcefully delivered by the winds, by passing the Bankhead-Jones Farm Tenant Act. The act was a first step in taking submarginal, highly-erodible land out of cultivation. The act helped financially strapped farmers by purchasing from them poor farmland in dire need of restoration. Millions of acres were purchased, and by 1953 around 7 million acres of these lands were assigned to the U.S. Forest Service. In 1960, some of the 7 million acres were organized as national grasslands, including the Sheyenne National Grassland.
Today, the Sheyenne National Grassland supports an interesting mix of grassland species. Besides isolated remnants of native tallgrass, exotics such as brome grass and Kentucky bluegrass thrive. While these exotics carry some value as forage for cattle - annually stocked at about 10,000 head over a six-month period - these exotics also edge out native plants and are usually an impediment to restoration of tallgrass prairies.
Leafy spurge, a noxious weed that even cattle won't eat, is another foreign invader. Eurasian in origin, leafy spurge was first discovered in North America in Massachusetts in 1827. It eventually found its way onto the Great Plains, where it has really wreaked havoc. About 11,000 acres on the Sheyenne National Grassland is infested with leafy spurge, much to the consternation of grassland employees. An aggressive control program is underway, which includes use of herbicides and insects that attack the weed.
Another program the forest service uses is prescribed fire. As many as 2,000 acres are burned on the Sheyenne National Grasslands each year, less in wet years. Fire reinvigorates native grasses and burns off woody species, like the exotic Russian olive, which encroaches on tallgrass vegetation in the absence of fire.
|The sandy soils of the Sheyenne Grassland are susceptible to wind erosion and under conditions of drought or intensive grazing are slow to revegetate.|
Prairie landscapes are shaped by disturbance regimes, like drought, fire and grazing. A hundred and thirty years ago, that meant wildfire and bison. On the tallgrass of the Sheyenne Delta, fire probably played a larger role than did bison in shaping the vegetative mosaic. Every three to five years, fire would sweep through the area, burning plant material, thus recycling nutrients into the soil and setting the stage for diverse, healthy plant growth. Now, after more than a century of fire suppression, the forest service is recognizing the positive benefits provided by controlled burns, and is using fire as a management tool.
The grassland is also home to the western prairie fringed orchid. While this native may be faring well - actually increasing in number on the national grassland - it is still a federally-listed threatened species. The Sheyenne National Grassland contains one of only three surviving meta-populations of the orchid in North America.
Another important species is the greater prairie chicken. Less than 200 chickens still survive on the grassland and their numbers are declining. Their ultimate survival may depend on successful restoration of native vegetative habitat. The forest service has been trying to address this issue, but has met with only limited success.
Perhaps one of the most remarkable scenic qualities on the Sheyenne is its undulating sand-dune landscape of oak savannah. According to "Badlands on the Brink," the 1993 booklet published by a consortium of land and wildlife interest groups, nationally less than one percent of the original 30 million acres of oak savannah is still relatively unaltered. Oak savannah, a vegetative characteristic of some tallgrass prairies, is extremely rare. And no oak savannah is represented within the National Wilderness Preservation System.
|Bur oak make up the Sheyenne's rare oak savannah landscape. However, leafy spurge (green-yellow flowers in foreground) is pushing out native vegetation in many areas.|
That's why some groups are calling for a portion of the oak savannah to be included in the wilderness system. The forest service is currently studying roadless areas on the Sheyenne National Grassland, and will consider a recommendation to Congress as part of its Forest Plan Revision process (see sidebar story).
Currently, the Sheyenne River is also being studied for its eligibility in the National Wild and Scenic River System. Already designated as a state wild and scenic river, approximately five miles of the Sheyenne flows through or borders lands directly administered by the forest service. Although many already enjoy the scenic nature of the river - canoeing its course, for instance - whether it qualifies for inclusion in the national river system is yet to be determined. The river is lined by a riparian forest of basswood, American elm, green ash and bur oak. American elm has been significantly damaged, however, by Dutch elm disease.
The forest service is considering special management for four sites with unique botanical qualities. These sites, ranging in size from 80 to 400 acres, contain characteristics particularly remarkable for their tallgrass and oak savannah qualities. Habitats, including choppy and hummocky sandhills, wet meadows and swales would be represented.
While livestock grazing and recreation - including bird watching, hiking and horseback riding - will continue to play large roles on the Sheyenne National Grassland, public land managers are now making tallgrass restoration an equally important priority. Although not an impossible task, restoration is still a large one. But there's hope. Whereas it may take generations to restore old-growth forests after timber cutting, restoring prairies can be accomplished much faster. Some prairies can reclaim many of their native qualities in as little as 10 years.
|The Sheyenne Grassland is home to the western prairie fringed orchid, a federally-listed threatened species.|
But major obstacles to tallgrass restoration on the Sheyenne National Grassland remain: the relentless invasion of noxious weeds like leafy spurge, the encroachment of exotics like Kentucky bluegrass, and a shortage of money, personnel and time to make restoration happen. But if the forest service doesn't take the lead, then who will? If action isn't taken now, how long before the tallgrass is changed beyond recognition?
Tallgrass is indeed teetering on the brink as we approach the next millenium. If it's to be saved, the public must respond. That means cooperative interest and involvement, from state citizens, environmental groups, area farmers, stockmen associations, state and federal governments and agencies. Barring that, even "postage stamp" remnants of the great tallgrass prairies may vanish.