past in place for others to enjoy! to others for place in past and employer. and Please leave all relics of the the of relics all leave Please (202) 720-6382 (TDD). USDA is an equal opportunity provider provider opportunity equal an is USDA (TDD). 720-6382 (202) Washington, D.C. 20250-9410, or call (800) 795-3272 (voice) or or (voice) 795-3272 (800) call or 20250-9410, D.C. Washington, Director, Office Of Civil Rights, 1400 Independence Avenue, S.W., S.W., Avenue, Independence 1400 Rights, Civil Of Office Director, and TDD). To file a complaint of discrimination, write to USDA, USDA, to write discrimination, of complaint a file To TDD). and your discovery! your should contact USDA’s TARGET Center at (202) 720-2600 (voice (voice 720-2600 (202) at Center TARGET USDA’s contact should and trackways await await trackways and tion of program information (Braille large print, audiotape, etc.) etc.) audiotape, print, large (Braille information program of tion rock. Toadstools Toadstools rock. - communica for means alternative require who disabilities with and over sandstone sandstone over and program. (Not all prohibited bases apply to all programs.) Persons Persons programs.) all to apply bases prohibited all (Not program. of an individual’s income is derived from any public assistance assistance public any from derived is income individual’s an of through gullies, gullies, through genetic information, political beliefs, reprisal, or because all or part part or all because or reprisal, beliefs, political information, genetic along streambeds, streambeds, along of years ago. years of status, familial status, parental status, religion, sexual orientation, orientation, sexual religion, status, parental status, familial status, that, the trail winds winds trail the that, national origin, age, disability, and where applicable, sex, marital marital sex, applicable, where and disability, age, origin, national capture what life was like in this ancient river valley millions millions valley river ancient this in like was life what capture cessible. Beyond Beyond cessible. tion in all its programs and activities on the basis of race, color, color, race, of basis the on activities and programs its all in tion once soft mud. Scientists have pieced these clues together to to together clues these pieced have Scientists mud. soft once - ac universally - discrimina prohibits (USDA) Agriculture of Department U.S. The bizarre beasts are bits of bone and tracks imprinted in the the in imprinted tracks and bone of bits are beasts bizarre unravel the park’s mysteries. The first 1/4 mile of trail is is trail of mile 1/4 first The mysteries. park’s the unravel even rhinoceroses roaming here. All that remains of these these of remains that All here. roaming rhinoceroses even Follow the trail markers along the mile-long loop trail to to trail loop mile-long the along markers trail the Follow iature horses, humpless camels, gigantic tortoises, pigs, and and pigs, tortoises, gigantic camels, humpless horses, iature www.fs.usda.gov/nebraska - min find would you and years Great Plains animals. Plains Great Turn the clock back 30 million million 30 back clock the Turn and erosion exposed the record of North America’s early early America’s North of record the exposed erosion and (308) 432-0300 (308) the rock into badlands. These geologic processes preserved, preserved, processes geologic These badlands. into rock the Chadron, NE 69337 NE Chadron, abundant life it once supported. once it life abundant the rocks you see today. Over time, water and wind sculpted sculpted wind and water time, Over today. see you rocks the rock-strewn gullies disguise the the disguise gullies rock-strewn 125 North Main Street Main North 125 current carried volcanic debris that, layer upon layer, formed formed layer, upon layer that, debris volcanic carried current braska. Yet its barren hills and and hills barren its Yet braska. Pine Ridge Ranger District Ranger Ridge Pine to drink on the shores of this broad shallow river. The water water The river. shallow broad this of shores the on drink to - Ne in place other no like is Nebraska National Forest and Grasslands and Forest National Nebraska It was hot and muggy when these prehistoric mammals came came mammals prehistoric these when muggy and hot was It scape you are about to explore explore to about are you scape “A River Ran Through It” Through Ran River “A - land other-worldly stark, The For More Information Contact Information More For Welcome to Toadstool Geologic Park Geologic Toadstool to Welcome 1. Why is it called Toadstool? Notice the dark, jagged gravel beneath your feet. This between tracks made by the same foot. Changes in travel 4. Water’s Cutting Edge desert pavement is a coarse mixture of silicon dioxide (the speed are shown by lengthened or shortened strides. The first visitors here in the late Over time rushing water has cut away the under- same compound as glass) and fossil bone fragments. 1800s must have felt they were Compare the photograph to side of this cliff. When the bank is undercut enough, travelling through a land of gi- the large rock off to your the weight of the overhead mass breaks off in large ant mushrooms. They fancifully right. Can you see the tracks chunks, crashing into the streambed and diverting the labeled the jumble of sandstone of a four-legged animal stream flows. These badlands erode away at an average slabs resting upon their clay pil- as it made its way across of an inch per year. How much change has occurred lars, toadstools. The name stuck. the mud, now hardened to since you were born? stone? Close inspection of Toadstools are created by the Seasonal flooding filled prehistoric tracks with mud the tracks shows the foot forces of wind and water, eroding and silt, preserving then. What tracks will you leave had two toes. Its size and the soft clay faster than the hard sandstone rock that for future visitors to discover? shape are consistent with the caps it. Erosion eventually collapses the giant toad- entelodonts (giant pigs) of stools while new ones are forming. the time. Keep looking. You may see other tracks. 2. Travel Over Gravel Notice the bone protruding out of the ground? The pen in the photo is there to show the relative size of the bone. Volcanoes to the west periodically blanketed this area with ash. Water from rain and snow dissolved the ash Can you detect the bone chips, or fossil fragments? and seeped into cracks in the clay, where it crystal- lized. The width of the cracks is the thickness of the 3. Pocks in the Rocks? gravel pieces. As clay eroded, the hardened minerals No, they’re tracks! Tracks are distinguished from other de- and bone fragments of long dead animals became pressions in the rock because they do not occur randomly. exposed. These were made by animals living about thirty million years ago. The toes point in the direction of travel. The size and depth of the tracks indicate the size and weight of the animal that made them. The stride is the distance 5. Whose Fault Is It? 6. Cliff Clues 7. Prehistoric Pictures As the rock cliff is undercut by erosion, overhanging By now you’ve noticed rocks break off. When will the next break occur? Since two kinds of rock: a light no one can predict this, please view the cliff from a safe buff-colored claystone and distance. a darker sandstone. The claystone is softer than the Up the draw sandstone. The sandstone from the cliff was formed as a sandbar (south), tiny in the river that flowed 30 toadstools million years ago. Wild- continue to take life attracted to the water shape as the left their tracks in the wet relentless pro- sand, some of which were Well, no one’s really! A geologic fault occurs when age, notice the horizontal band of rocks in the cliff face. The cess of erosion preserved and are now vis- underground stresses cause the earth’s crust to fracture. band ends suddenly, then continues on approximately 30 feet continues. ible today. Small shifts may go unnoticed, while large movements lower. Could you have felt this “shift” that occurred between In the photo are webbed cause major earthquakes! Rock layers and colors abruptly 8 and 2 million years ago? tracks left by prehistoric change at the fault line. Looking west across the drain- ducks. Can you picture The geologic processes that created the ancient them sunning, preening, This area requires scrambling up the rocks and a steep river, attracted animals to it, and exposed their and dabbling for food walk back to the trail – proceed with caution! ancient tracks, are still at work today. What on the shore millions 8. Rhinos’ Right-of-Way tracks will be captured today for tomorrow’s of yeas ago? Unfortu- This trackway, extending nearly 3/4 of a mile, visitors to find? Will scientists one day ponder nately, these tracks were The evidence of this migra- documents one of the longest record of prehistoric the traces of our actions here? vandalized, destroying tion is unique. For this time mammals in North America 30 million year ago. information about the period in North America, Even though the footprints are not clear, the pat- animals that left them. this is the longest and most terned imprints tell a story of prehistoric migration. diverse known trackway. Back to Basics: The trackways can best be Research on the trackway indicates: the tracks These terms of the trade will help you understand your prehistoric seen in the early morning paralleling the streambed belong to two species of Missing Pages journey through Toadstool: rhinoceros that used the stream as a path.