3. Savanna Savanna Trail Savannas are grasslands interspersed with trees and maintained Nickel Preserve 1. Ozark Geology by fire. They are generally characterized by canopy covers of less The Ozarks consist of a dome that has been slowly uplifted and than 50%, usually comprised of oaks and pines with a few hickories. SELF-GUIDED TRAILS eroded, resulting in a pattern of rolling plains to highly dissected hills Savannas can be transitional areas between prairie and forest, but with deeply entrenched valleys. Its unique geological history has led to they are always undergoing successional change. Varied topography a diverse landscape comprised of a great variety of plant communities. would naturally tend to favor open woodlands and savannas on the A major reason for the region’s high biological diversity is that parts of drier ridges and south- & west-facing slopes. Such areas would be the Ozarks have been continuously available for plant and animal life characterized by a diverse and highly productive understory of grasses since the late Paleozoic, some 230 million years ago, and constitute and forbs. perhaps the oldest continuously exposed land mass in North America. Savannas are among North America’s most imperiled ecosystems. Soils throughout the preserve are very thin, with a layer of chert Conservation scientists estimate that these unique systems have gravel several feet thick that overlies a layer of limestone. The undergone greater than 99% decline from their original coverage. dissolution of this limestone layer has formed several caves throughout Agricultural conversion and development have eliminated most of our the preserve. Alternating beds of shale and sandstone occur beneath these layers. The Burgen Sandstone that occurs at the surface along original savannas. Those areas that avoided development quickly SELF-GUIDED TRAILS the Illinois River dates to over 450 million years old. The rugged became dense, closed canopy forest in the absence of periodic fires. Trail markers Selective thinning and prescribed burning are being used to restore Preserve Headquarters topography has spared much of the area from conversion to agriculture Trailhead and other development. savannas to a few of the places where they once occurred. Trails This brochure serves 4. Oaks Roads 2. Fire as a guide to the Fire is believed to have been a frequent and widespread ecological Oaks are the dominant and single most important group of trees for Savanna Trail and process that profoundly shaped the natural communities of the wildlife in the Ozarks. They provide nesting sites for birds and food for For further information about the Pine Ridge Ozarks. Prior to the settlement of Indian tribes in the mid-1800s and numerous animals. Their hollow logs provide denning opportunities The Nickel Preserve and The Nature Conservancy Trail, both of which subsequent settlement following the Land Run and statehood, the to many wildlife species including squirrels, chipmunks, raccoons, please contact the begin at the Nickel region had a history of frequent fire. In addition to lightning-set fires groundhogs, and opossums. Preserve Manager at (918) 456-7601 or that most often burned in the spring and summer, native Americans Oak acorns are a critical fall and winter food source for deer, turkey, Visit or website at www.nature.org/oklahoma Preserve Headquarters. are known to have set fires each autumn. Fires were set to improve squirrel, and other small mammals. Acorns are a type of hard mast, You may wish to hike forage for wildlife, to drive one or both of the trails. as are walnuts and hickory nuts. Soft mast includes the fleshy fruits of herds, increase visibility, flowering dogwood (Cornus florida)., black cherry (Prunus serotina), Along the trails you will increase plant diversity for and persimmon (Diospyros virginiana). foods & medicines, and find numbered posts which The oaks are divided into two broad groups---the red oaks and coincide with the narrative many other uses. Historical evidence the white oaks. Northern red oak (Quercus rubra), southern red oak in this brochure. suggests that Ozark (Q. falcata), shumard oak (Q. shumardii), scarlet oak (Q. coccinea), These are good landscapes have changed black oak (Q. velutina), and blackjack oak (Q. marilandica) are all places to stop dramatically in the absence members of the red oak group that occur here. The red oak group is of periodic fire. Early distinguished from the white oak group by the bristle-tipped lobes on The Nature Conservancy and observe descriptions of the region leaves, hairy inner surface of the acorn nut (the nut must be broken Oklahoma Chapter the plants and consistently noted open 2727 E. 21st Street, Suite 102 animals around you. to observe this trait), and acorns that require two years to mature. Tulsa, OK 74114 prairies, grass-covered Because they require two years to mature, tiny first year acorns occur savannas, and very open on mature trees along with the larger second year acorns. Acorns of (918) 585-1117 Please observe (918) 585-2383 fax woodlands with abundant herbaceous ground cover. The frequency, the red oak group are usually bitter and are less desirable to wildlife. the following rules and recommendations when hiking trails: seasonality, and intensity of fires would likely have varied widely for The bark of many of the oaks in the red oak group is darker than that any given site. This would have led to a diverse landscape comprised of trees in the white oak group. 1. Be Prepared. Bring water, apply insect repellent and of a mosaic of vegetation types including prairie, shrubland, savanna, White oak (Q.alba), post oak (Q.stellata), bur oak (Q. macrocarpa), woodland, and forest. sunscreen as needed. Know your abilities, and do not overexert. and chinkapin oak (Q. muehlenbergii) are all members of the white Funding for the printing of this trail guide is generously provided through This part of the preserve has a recent history of intense fires that oak group occurring on the preserve. The white oak group has leaves a Conservation Education Initiative grant from the Kirkpatrick Foundation, 2. Do not pick flowers. Leave the trail as you found it. Do not followed an herbicide application. The grasses and forbs characteristic encouraging children, parents and traditional and non-traditional educators to with rounded, not bristle-tipped lobes. The inner surface of the acorns take plant or animal parts, rocks, or any other items. of tallgrass prairie and savanna emerged following the opening of the connect with nature. For more information about the Conservation Education canopy by the fire. These savannas will now be maintained through is smooth, and acorns are produced every year. The acorns are Initiative, please go online to www.nature.org/oklahoma . 3. Do not wander away from trail. Tall grasses and brush may periodic prescribed burns conducted by Conservancy staff. usually somewhat sweet and are among the first to be consumed by wildlife. Post oak and white oak (as well as blackjack oak from the red conceal hazards such as snakes, biting or stinging insects, ticks, Long viewed as a catastrophic, destructive force on the landscape, fire is increasingly being recognized as a natural process essential for oak group) are often dominant trees in fire-maintained savannas and Cover drawing by Ernest P. Edwards, poison ivy, rocks and holes. Inside drawings by Robert Savannah the existence of some of our most imperiled natural systems. woodlands. 5. Savanna Wildlife slowly evolve toward forest until the next disturbance renews the cycle forests don’t burn frequently, leaf and needle litter accumulates to D. Oak-Pine Forest Savannas and open woodlands harbor an impressive amount of once again. depths that hinder pine seedling establishment. Occasional fires kept Forests, as opposed to more open woodlands, have a closed canopy natural diversity. They seem to capture much of the diversity of both 7. Woodland the litter from becoming too deep for shortleaf pine to regenerate. and a thick understory. Forests on the preserve are dominated by oak forests and prairies, while providing ideal habitat for a suite of “savanna Areas with more trees than savanna but with sparser canopy than Because fires have been suppressed for several decades, the and pine. Multiple layers of canopy trees and shade-adapted shrubs specialists” forest are considered to be woodland. Woodlands exhibit the same structure and composition of pine-dominated forests and woodlands of and saplings occur. These forests often contain more fire-sensitive More than 40 species trees found in savannas, but at higher densities. The frequency and the Ozark region are much different than they were in the past. Early trees and shrubs, such as northern red oak, sugar maple (Acer of breeding birds use intensity of fire determines where a plant community lies between travelers and settlers in the region described very open pure pine saccharum) and flowering dogwood. savannas for their savanna and forest. woodlands with a diverse and abundant understory of grasses and A diverse mix of deciduous trees and shrubs occur on the various habitat needs. Woodlands are characterized by productive understories of woody forbs. Blueberry or huckleberry (Vaccinium spp) still remain in the slopes and bottomlands in the Ozarks. In addition to the dominant The most open shrubs, grasses, and forbs. Hazelnut ((Corylus americana), buck understory of these woodlands, but productivity of berries has nearly oaks and hickories, look for elms (Ulnus spp), blackgum (Nyssa areas may harbor brush (Symphoricarpos orbiculatus), and sprouts of oak and hickory ceased beneath closed canopies. sylvatica), sassafras (Sassafras albidum), serviceberry (Amelanchier kingbirds, field occur in the understory here. A variety of woodland wildflowers occur Nickel Preserve staff are restoring areas of pine woodland and arborea), rusty blackhaw (Viburnum rufidulum), and huckleberry sparrows, and throughout, including the rare royal catchfly (Silene regia), a sun-loving savanna throughout the preserve.