Ice Age

Wisconsin's Glacial Landscape A mere 15,000 years ago, during the Ice Age, most of northern North America lay under the grip of colossal ice sheets. The eff ects of the advancing and retreating glaciers can be seen in the headlands of Cape Cod, the Finger Lakes of New York, and the hills o f M ichigan, but nowhere is the g lacier' s mark upon the land more im pressive than in W isconsin. Indeed, the State has lent its name to the most recent series of glacial advances and retreat s--the W iscon sin Glac iation lasting from about 100,000 t o 10,000 years ago. Many times during the past two mill ion years, a time also known as the Pleist ocene Epoch, the climate has fluctuated between warmer and cooler temperatures . During the colder fluctuations, glaciers formed and spread outward from Arctic areas , engulfing most o f northern North America. Each of the major glaciations has been followed by a warmer interglacial period, probably similar to that of today , during which the glac iers melted away. The glacier most recently flowed into Wisconsin about 2 5,000 years ago and reached its greatest extent, covering approx imately twothirds of the State, about 14,000 to 16, 000 years ago before melting back. The retreat of the ice front was interrupted a number of times by readva nces; the last one touched northwestern W isconsin about 10,000 years ago. The extent of this and earlier glaciations in Wisconsin is shown on the maps on this brochure. distances are called errat ics. The material frozen into the base of the flowing ice gouged and scraped th e land, leaving in some areas scratches, called striations , in the bedrock . In other areas stream lined , elonga te hills called drumlins were formed . Wisconsin's stat e capitol sits atop one of these hills. Impressive clusters of them are fou nd in the Campbellsport Drumlins Unit of the Ice Age National Scientific Reserve and in other areas, particularly southeast ern W isconsin The striations and the long axis of the drum lins indicate the direction the ice flowed. W hen the ice melted at the edges of the lobes the sand , silt, cobbles , and boulders frozen in it were released and formed ridges called moraines. Even as the glacier melted back, ice usually contin ued to flow toward its edge, bringing mo re debris w ith it. Occasionally the f low stopped, the ice stagnated , and blocks of ice detached from the glacier were buried in debris. Many of Wisconsin 's lakes lie in the depressions formed by the melting of the buried ice . The mora ines vary greatly across the state. Those in the southwest are usua lly dry, narrow ridges sitting atop the older hills at the edge of the unglaciated Driftless Area. Across the northern counties the moraines form a broad band The advancing ice was channeled into the lowlands now occupied by Lakes Superior and M ichigan, Green Bay, and the Fox River, and it was impeded by the uplands of the Bayfield, Keweenaw, and Door Peninsulas. The ice was thus split into six m3jor lobes as it flowed across the state . The Green Bay Lobe, which had few obstructions in its path, penetrated as far south as present-day Janesville in Rock County. The ice within the lobes was almost always sliding or creeping toward the edges of the glacier, even as it melted. As the ice moved it froze around grains of sand, pebbles, and boulders , picked them up, and carried them along. Boulders that were ca rri ed great of hills and hollows - a poorly drained rocky landscape dotted w ith lakes, marshes , and bogs. The Chippewa Moraine Ice Age Reserve Unit is a particularly picturesque portion of these moraines, containing numerous depressions fi lled w ith lakes, bogs, and marshes . The moraine in Waushara County in the center of the state is similarly pitted with thousands of these depressions, but most of them are dry. Th e rugged, scenic Kettle Moraine in the eastern part of the state is actually a series of moraines formed between the Lake Mic higan and Green Bay Lobes. The Green Bay Lobe also lef t a moraine in Sauk County which bloc ked both ends of a gorge in the Baraboo Hills creati ng Devils Lake. Some mora ines sta nd no more th an 30 feet above the surrounding terrain, but others in t he Kettle Moraine rise to heights of 250 t o 300 feet. of the glacier. Like drumlins, they are usually aligned para llel to the ice fl ow. The flowing meltwater spread fi ne layers of sand in broad pla ins, such as those in Langlade, Rock, and Portage Counties, that today are fertile cash crop farm ing areas . In se veral areas the meltw ater pooled , form ing large lakes w here silt and clay collected . The flat bed of glacial Lake Wisconsin , one of t hese lakes, is a marked contrast to the unglaciated hills of the Driftless A rea th at bound it s w estern side. In the Fox River valley, Lake Winnebago and Horicon Marsh are small remnants of anot her prog lacial lake--Lake Oshkosh . The torrents of meltwater released from the w asting glacier or draining glacial lakes cut spectacular gorges in several areas of th e state . Some, such as the Dalles of the St . Croix, the Wisconsin Dells, and the Dells of t he Eau Claire , are still occupied by streams . Ot hers, like the smaller gorge at th e Cross Plains Ice Age Reserve Unit , are now dry except for spring and storm run-off . Streams flowing over, under, and beyond t he glacier also left deposits that vary our landscape. The conical hills of water-rounded sa nd and cobbles called kames, that stud parts of the Kettle Moraine, are deposits of streams that flowed dow nward through cracks in the ice . The sinuous eskers, such as the one nea r th e - Although many of these featu res are outstanMondeaux Flowage in Taylor County and th e ding by t hemselves, seen as a w hole t hey form Parnell Esker in She boygan County, are ridges a glacial la ndscape of remarkable beauty. The of rounded sand and gravel deposited by thousands of drumlins, kames, and kettles and streams that flowed through tunnels at the base the numerous moraines, eskers, and other featu res left by the flu ct uating lobes of the last Wisconsin glac ier appea r very sim ilar to features being formed by glaciers active today. The region of recent glacia tion is dotted w it h over 14 ,000 glacial lakes, numerous bogs, marshes, and fens and many streams whose courses are determined by the y oung glacial deposits. In a sense, this reg ion of t he state is still recoveri ng from the melt ing of the last glacier. As the streams slowly wash away the kames, eskers, and moraines and the marshes, bogs, and lakes fill w ith sediment and organic debris , this young glacial landscape will become like the older glacia l landscape which lies betw een t he Driftless Area and the terminal moraines of the most recent g laciation. In the areas of W isconsin that were glaciated prior t o the most recent glaciation, erosion has had time to modify the landscape and, as a result, . glac ial landforms are subdued or streams into a maze of narrow, twisting ridges and valleys. There are few natura l lakes, bogs, or marshes in this part of the state Several prominent mounds, such as Blue Mound in easte rn Iowa County, stand as erosion remnants w ell above the surrounding plain . This Driftless Area landscape has been forming for m any thou sands of yea rs, wh ereas our most recent glac ial landscape is but 15,000 years o ld or younger. unrecognizable . Lakes and bogs are m uch less common in th is older landscape . Most have either been drai ned by gradually lengthening stream s or filled w ith sediment w ashed off the ridges and organic materi al from thousands of growing seasons. The result is a ge ntly rolling landscape or nearly flat plains broken by occasional remnant hills or ridges. The rem na nts of g lac ial de bris tel l us these areas w ere glac iated long ago , but relatively little is known about their glacial history. Wisconsin' s legacy from the glaciers and meltw ater streams of t he Ice Age is a landscape of great diversity and beauty The State' s many lake s and ponds, forested hill s and ridges , and gently roll ing farm lands rem ind us of th e glacier' s visit and beckon us to come, explore, and enjoy! In striking contrast to both of th ese glacial landscapes st ands the dry upland of sou thwestern W isconsin known as the Drift less Area . M uch of t his region is a ro lling upland plai n, w ith no glacial sed iment, that has been deeply cut by Glacial Lobes of the Wisconsin Glaciation I SUPERIOR '" I LOBE ,/ , \c ,' ,' __.,, . • CHI PPEWA LOBE ' ) I : I ,/ "" :/ LANGLADE LOBE / , I I , ,'.j. ,'/ I rJ ..... ..---/ lo GREEN BAY LOBE '---- • I I "' I I Ice-f low direction I I ~ •--""' I Maximum extent of ice during the last part of the Wisconsin Glaciation 125 ,00010,000 years ago ) I \ I I I The cutting of the Dalles of the St. Croix by water draining from Glacial Lake Superior Roche A Cri St. Croix Dalles Point Beach South Kettle Moraine North Kettle Moraine Blue Hills Gibralter Rock Nature Study A Trail To Explore The Glacial Landscape Imagine a public greenway meandering across W isconsin 's glacial landscape. Imagine a trarl 1000 miles long leading both to places of glacial beauty close to home and to some of the remotest parts of Wisconsin. That is what the late Ray Zillmer of Milwaukee had in mind in the 1950s w hen he pro posed that an Ice Age Glacier Nat ional Forest Park be established along the entire length of th e moraines marking the f urthest advance of the last glacier in Wisconsin. An avid hiker, he proposed a continuous foot path , similar to the Appalachian Traii, as the cemrai feature of the park so that visitors could explore and enjoy the glacial landscape at their own pace. In 1958 , the Ice Age Park and Trail Foundation was established by a group of Wisconsin citizens to promote the creation of the national glacial park. As the effort to w in Congressional Near Holy Hill Langlade County authorization for the park gained momentum , volunteers were already at work building the first segments of the future Ice Age Trail in the Kettle Moraine State Forest. In 1971, Congress established the nine-unit Ice Age National Scientific Reserve to be jointly adm inistered by the National Park Service and the State of Wisconsin. While the nine Reserve Units contain only portions of t he glacial park proposed by Zillmer, in the authorizing legislation Congress recognized the va lue of the continuous footpath, but ieft it ro the private citizens of W isconsin to complete the Ice Age Trail. With the formation of the Ice Age Trail Council in 1975, these efforts accelerated across the state. In a few years, the members of the coun cil were successful in establishing major segments of the trail. Through local chapters , Indian Pipe Chippewa Moraine Marsh Marigolds National Scenic Tra ils the tra il council works cooperatively w ith public age ncies and hundreds of private landowners to establish t he Ice Age Trail. Existing segments are maintained by the USDA-Forest Service, the Wisconsin Department of Nat ural Resources , county and municipal pa rk and forestry departments, and many private volunteers. Boy Scout and Girl Scout troops, 4-H and outing clubs , and many local civic organizat ions help the council maintain t he trail. In October 1980, Congress recognized the national significance of th e ice Age Trail and the efforts to establish it by designating it a Nati onal Scenic Trail (NSTl . The legislation assigned overall ad min istrative res ponsibility for the trail to t he Secretary of the Interior . The Nat ional Park Service administers the trail as a unit of the National Park System in cooperation w ith the W iscons in Depa r tm ent o f Natural South Kettle Moraine Resources , the Ice Age Tra il Counc il, and the Ice Age Park and Trail Foundation . Actual development and management of the trail w ill be accomplished t hrough these and many other cooperating Federal, St at e, and local agencies and private trail organizations. Approximately 160 miles of trail hav e been certified by the National Park Service as part of the Ice Age NST . Certification indicates the segment is developed and managed in accordance w ith the com prehensive management plan fo r the trail and entitles the segment t o be marked w ith th e official trail symbol. An add it ional 180 miles of uncertified segments are open to pu blic use. The official Ice Age NST sy mbol and a map showing the locations of existi ng and futu re segments of the trail are found on the reverse side of this brochure . Puffballs Menches Segment North Kettle Moraine Langlade County Enjoying the Trail Because many differenl public agencies and private interests are participating in the development and management of the Ice Age NST, users must be mindful that the type and width of the trail tread, the support facilities available such as campgrounds, and rules and regulations governing use of the trail will vary from segment to segment. Users of the Ice Age NST are urged to show their appreciation for the voluntary public and private efforts to develop and manage the trail by using it and related facilities properly and complying with any ap- Eau Claire Dells Helping Establish t he Trail information on which segments are open to other uses besides hiking , write to any of the addresses given below. plicable rules and regula- -t<,,___-'-'!~!l!l­ tions. Users should be especially careful to respect the rights of private property owners, particularly those who have generously allowed the trail to cross their land. Please stay on the trail, especially when crossing private lands. Trail Marking. Certified segments of the Ice Age NST are signed with the marker shown on the map side of this brochure. These are supplemented by paint blazes {usually yel low) and routed wooden signs that provide distance and directional information. Other segments are marked Pike Lake State Park similarly, but lack the officia l Ice Age NST symbol. Permitted Uses. All segments of the Ice Age NST are open to travel by foot for hiking and backpacking . Other nonmotorized uses, including bicycling, horseback riding, cross-country skiing, snowshoeing, and jogging, may be permitted on a given segment according to the desires and policies of the managing authority responsible for the segment. In addition, certain segments are open to snowmobiling in winter. For Fees and Permits. The use of some segments of the Ice Age NST and overnig ht facilities requires the payment of a fee and/or obtaining of a permit Bikers, for example, must purchase a State Trail permit from the Wisconsin Department of Natural Resources to ride the Ahnapee, Sugar River, Tuscobia, Military Ridge, and Drumlins State Trails segments of the Ice Age NST. Fees are also requ ired to camp in many developed Federa l, State cam grounds. Users should check with managing authorities in advance to determin e if permits and/or fees are required. .iill.Q_~ t y Camping. Facilities for camping along the Ice Age NST vary greatly. Some mana ging authorities permit camping anywhere along the trail Others permit camping only at designated sites. In some cases, the trail may already be open to use but designated camping sites have not yet been established. Along such segments 1t may be difficult to fi nd any place to camp legally Users are urged to plan their trip in advance to assure themse lves proper overnight accommodations . Patience is needed while the trail is being developed . Above all, avoid trespassing and violating private property rights. Interpretive Facilities. Major interpretive centers explaining the glacial history and geology of Wisconsin are located along the trail in the Northern Unit of Kettle Mora ine State Forest and Interstate State Park. Fishing. A Wisconsin fishing license is required for fishing in lakes and streams along the trail. Hunting. Many public ~ p r~ l a n ds through which the Ice Age NST passes are legally open t o hunting du ring the prope r seasons. It is not intended that passage of the trail through these lands should in any way lead to their closure to hunting. Similarly, passage of the trail through lands closed to huntin g does not open them in any way to hunting. In general, the trai l will re main open to use during hunting seasons . However, some segments of the trail may be closed to use during some hunting seasons by the managing authorities responsible for those segments. Trail users should check in advance wi th the managin g au thorit y regarding use of specific trail segments during hunting seasons. Trail use rs are encouraged to wear " hunter' s orange" while using segments open to hunting. Additional Information. For specific information on segments of the tra il on State lands, wr it e to : Wisconsin Department o.f Natural Resources, Box 7921, Madison, WI 53707. Information on t rai l segmen ts on county, municipal , and private lands can be obtained from the Ice Age Tra il Council, 2302 Lakeland Avenue, Madison, WI 53704. Information on the segment in t he Chequamegon Nation al Forest can be requested from the Medford Ranger District, Chequamegon National Forest, P.O. Box 150, Medford, WI 54451. Requests for additional general in formation about the trail may be addressed to: Ice Ag e Nationa l Scenic Trail , National Pa rk Service, 1709 Jackson Street, Omaha, NE 68 102. While most parts of the Ice Age Trail that cross public lands have been completed, the major portions of the trail that must cross private la nds remain to be developed. Your help is needed in establishing additional segments of the trail. You can help by joining the Ice Age Trail Council and its local chapters and volunt eering to assist in the effort to establish and maintain the trail. Donations of money, land , and easements for the trail are also needed. You can help complete the trail by giving a taxdeductible gift of this type to the non profit Ice Age Park and Trail Foundation, 780 North Water Street, Mi lwaukee, WI 53202. , Apostle Islands National Lakeshore ,. SCALE 0 10 20 1:1 ,187, 648 30 40 O c:=:::i 10 = =2I0 ==3I0==4c O=:::r50'.:::::=J 60 KILOM ETERS .!,./ . .i I k~ LEGEND Ice Age National Scenic Trail ..... Certified segment Other segment .....--....... __ Proposed segment ..,,,,,,.--- State trail North Country National Scenic Trail /; Mill Bluff Ice Age National Scientific Reserve Unit /; Peninsula Selected State Park - - Selaeted-Cetmty, State, or Nationa~ Fc~est National Park Service Area Glacial lake Extent of last glaciation Maximum extent of earlier glaciations This brochure has been prepared cooperatively by the National Park Service, t he Ice Age Park and Trail Foundation, and the Wisconsin Department of Natura l Resources, w ith assist ance from the W isconsin Geological and Natural Hist ory Survey and t he University of Wisconsin Cartographic Laborat ory. Shaded relief from: Land Forms of Wisconsin;© 1971, Regenls, University of Wisconsi n; courtesy of; University of Wisconsin-Extension, Geological and Natural History Su rvey. Funds for printing this brochure were donated by Fort Howard Paper Company , Green Bay, W isconsin . It was printed at cost by Neyler Color-Lit h Company, Wau kesha, Wisconsin. ___ ________ ,, .,._ ------------------- ---- - --~- -- _______ _.. ~~~- - - - -- --- -- -- --- - - - -- - - --- - ---- - - - - -- - - - - - - - - - - - - - - ------ -------·-- Description of the Trail Route The route of the Ice Age National Scenic Trail generally follows the end moraines of the most recent glaciation, although it diverges from t hem in several areas to include other features of the g lacial landscape and a glimpse of the Drihless Area. Fro m its east ern end at Potowatomi State Park on Green Bay, the tra il route follows in places t he present and former shorelines of Lake Michigan, the crests of eskers, and the edges of bogs in Manitowoc County. In several long existing segments and in many short ones, the trail continues over the rolling upland of the Kettle Moraine on public and private lands for more t han 100 miles th rough Sheboygan, Wash ington , and Waukesha Count ies. From marshes to hilltop remnants of prairie oakopenings and along wate rways thro ugh oak, hickory, and maple forest, the trail route threads its way among the many towns and vi llages of the densely popu lated southeastern portion of the state . Across Rock County the trail route follows railroad corridors north of the end moraine and city parkways through Janesville. In Green County a segment of the trail fol lows the Sugar River State Trail, affording an opportunity to explore the eroded remnants of features left by glaciers prior to the most recent W isconsin Glaciation. The trail route returns to the end moraine of the rece nt glaciation in Da ne County, skirts Madison's western edge, and leads to several glacia l meltwater channels cut into the bedrock hi lls of the Driftless Area, such as the one in the Cross Plains Unit of the Ice Age National Scientific Reserve. The resistant quartzite of the Baraboo Hills halted the glacier's advance in Sauk County and provides t he greatest relief found along the tra il-- over 800feet. Passing the Dells of the Wisconsin River, which were formed by glacial meltwat er, the tra il route crosses the flat bed of glac ial Lake Wisconsin in Juneau and Adams Counties, passing sandstone buttes rising among scrub oaks and jack pines. Crossing back into the hummocky topography of the moraine in Waushara County, the trai l route winds among numerous kettles and follows the Mecan River and several other trout streams. The route swings east along moraines deposited as the glacial margin retreated, passes through drumlin fie lds and among kettle lakes in Portage and Waupaca Counties, and then heads west before going north agai n across outwash plains and end moraines in Marathon County . In Marathon County and the counties to the north and west, long segments of the trai l have been establ ished on county forest lands. In Lang lade County, amid the spruce, fir, maple, and birch of the northern forest, the trail enters a region full of lakes and bogs formed by the melting of the g lacier. The moraine is so rough and has so many wet areas that frequent ly the trai l crosses beaver dams to pass through the swamps . In the lake-sprinkled Harrison Hil ls of Lincoln County the highpoint of the trail, 1875 feet, is reached on t he shoulder of Lookout Mountain . While walking the crests of eskers 1n the Chequamegon National Forest in Taylor County, one gets a hint of wha t was once the great wh ite pine and hem lock forest that provided the lumber to build the cities of the Midwest and the tanbark for the leather industry in the late 19th and early 20th centuries. In Chippewa County the trail again winds among numerous lakes and bogs in the moraine of the Ch ippewa Lobe. Bearing north, the tra il goes over the high quartzite shou lder of the Blue Hills in Rusk County am id small streams in an ash, birch, and maple forest. The northernmost point of the trail is reached in southeastern Washburn County along the Tuscobia State Trail at the Red Cedar River. The trail w ill wend its way through the dairy country of Barron and Polk Counties to its western end in the Interstate State Park Ice Age Reserve Unit at the Da lles of the St. Croix River.