Chapter 1
Minnesota: Land of Transitions
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For archaeologists, Minnesota is both a perplexing and an intriguing state to work in. Its vegetation cover grades into boreal coniferous forest to the north, tallgrass prairie to the west and southwest, and deciduous forest to the east and southeast (Figure 1.1a, Figure 1.1b, Figure 1.1c). While famous for its 10,000 lakes, it is crossed and bordered by streams that flow in these same directions. Streams in the southern and southeastern part of the state like the Minnesota, Blue Earth, St. Croix, and Root flow into the south-flowing Mississippi River. Streams on the Coteau des Prairies in the southwestern corner of the state, such as the Rock, flow southwestward into the Missouri drainage. And streams to the north like the Rainy, Red River of the North, Big and Little Fork, and St. Louis drain either northward into Hudson Bay or eastward into Lake Superior. Phrased another way, Minnesota is the only state having drainage to the Gulf of Mexico, through the Gulf of the St. Lawrence, and to the Arctic Ocean (Figure 1.2a, Figure 1.2b). Because of this confluence of major waterways and ecological communities, Minnesota was a melting pot of pre-European contact cultures– a peculiarity of its history that we explore in some detail in Minnesota Archaeology: The First Thirteen Thousand Years.
Chapter 1 provides an overview of the land, climate, and weather of this melting pot. Before we begin we must remind ourselves that people live in cultural landscapes, not natural landscapes. A cultural landscape is a geographical space suffused with cultural practices and understandings. Besides raw nature (lakes, rivers, vegetation, animals, rocks, and soil), it contain towns, travel routes, economic practices, social and political relationships among people, and individual people’s understandings of these places, things, and relationships. When Minnesotans think of “up north,” they have mental images of pine forests, snow, skiing, resorts, the fish-that-got-away, and towns like Ely and Grand Marais. To get “up north,” they drive up Interstate 35 or state highways 10 or 169. When they think of western Minnesota, they have images of prairie farmland, corn, tree-lined lakes, and towns like Worthington and Marshall. To go west, they drive down Interstate 35 to Interstate 80, go straight west on Interstate 94, or take state highway 7. If they think of northwestern Minnesota at all, they have images of a vast wetland with a sprinkling of crossroad villages and few roads.
Archaeologists study cultural landscapes by the material imprint, or signature, that people leave on the surface of the earth. When future archaeologists excavate present day Minnesota, they will concentrate on our material imprint on the land surface – on our towns, cities, roads, resorts, ski slopes, fields, and roads – and try to reconstruct our landscape from these places and their visible interconnections. In later chapters, we pay particular attention to the material imprints and cultural landscapes of the state’s precontact native peoples. In this chapter we concentrate on the “raw physical environment” part of these landscapes, that is, on the state’s large-scale resource zones, as they existed in the 1850s.
The Land in the 1850s
At 86,943 square miles, Minnesota is the twelfth largest of the 50 states. Bordered by Canada on the north, Iowa on the south, Wisconsin and Lake Superior on the east, and the Dakotas on the west, the state is about 400 miles long and 250 miles wide. It is a relatively flat state as evident in the difference between its highest point (Eagle Mountain at 2,301 feet above sea level) and its lowest point (at Lake Superior at 602 feet above sea level), both of which are in northeastern Minnesota.
Besides its snowy, cold winters, Minnesota is famous for its “10,000” lakes and numerous rivers and streams.2 Today, the total surface water area of the state including wetlands is about 20,526 square miles. About 4,000 square miles of this surface water are deep-water lakes and rivers, and 14,537 square miles wetlands (in the 1850s there were about 29,062 square miles of wetlands in the state). Minnesota’s 21,200 miles of historic drainage ditches are just one measure of the effort made to drain its surface water (Figure 1.3a). Some lakes in the southern, agricultural part of the state, such as Great Oasis, were completely drained for farmland in the late nineteenth and early twentieth centuries. The figure in the paragraph shows a typical attempt to drain a wetland.
Of the state’s 11,842 lakes ten acres or more in size, the six largest are “up north” (Table 1.1). The four counties that have no natural lakes (Mower, Olmsted, Pipestone, and Rock) are all in the lower two tiers of counties (Figure 1.3b). Its largest border lakes are Lake Superior (31,820 square miles) to the northeast and Lake of the Woods (1,485 square miles) to the north. Minnesota’s 6,564 natural rivers and streams flow a combined 69,200 miles, with that part of the Mississippi River entirely within the state the longest river at 680 miles (the Minnesota River is about 370 miles long).
Minnesota’s numerous lakes and wetlands, and its relatively flat surface, are a result of the advance and retreat of glacial ice. Beginning about two million years ago, glaciers flowed southward over the state at least four times. Since most of the surface features formed during the first three surges are either buried beneath more recent glacial deposits or have been scoured away, the composition of its current surface is mostly a result of the withdrawal of the last glaciers during the Wisconsin Glaciation. The Wisconsin glacier, which began its retreat about 19,500 B.C., left an intricate pattern of land forms, such as moraines, drumlins, and eskers, and a patchy but closely woven blanket of lakes, streams, and wetlands.
To bring some order to the complexities and nuances of Minnesota’s transitional physical environments, we divide the state into five primary resource zones, a northwest, northeast, central, southwest, and southeast (Figure 1.4). These resource zones are based on hydrologic features (presence or absence of lakes, lake morphology, and lake depth), and on the distribution of plant and animal communities, that have been more or less stable for about the last 4,500 years (the Late Holocene), the period during which most sites in the state’s archaeological database were formed. We also divide these zones into nine secondary regions to provide a finer scale of reference and comparison.
Northwestern Minnesota
As the last glaciers moved northward across the state’s northern border between 12,000 and 11,000 B.C., the outflow of the accumulated meltwater was blocked by the Canadian ice mass to the north and by a moraine dam to the south near Browns Valley. Unable to flow northward or southward, the water pooled, forming glacial Lake Agassiz.5 At its greatest extent the lake covered about 123,520 square miles of north-central North America. Its legacy in Minnesota is a huge, flat lakebed interrupted only by the incised valleys of meandering streams and by the former shorelines of the lake. Beach ridges are typically linear swells of sand and gravel 13 to 17 feet high and 500 feet or more in width. These ridges run in roughly parallel bands for miles across the surface of the region. The eastern arm of the lakebed stretches eastward to International Falls and the headwaters of Rainy River. Its southern lobe stretches down to Lake Traverse, which is the headwaters of the Red River of the North (Figure 1.5).
The southern lobe, which extends into eastern North Dakota and southeastern Manitoba, is bordered on the east by the Herman beach ridge and in the north by the Campbell beach (Figure 1.5a), both remnants of the last glacial advance (9500 - 9100 B.C.). Figure 1.5a shows the flat topography of the region, with the Campbell beach ridge in the background. Since all of this part of northwestern Minnesota is within the Red River drainage basin, we call it the Red River Valley region. It contains Clay, Kittson, Norman, and Wilkin counties, and parts of Marshall, Pennington, Polk, Red Lake, Roseau, and Traverse counties (Figure 1.5b). Many west-flowing rivers intersect the north-flowing Red. While lake basins are absent, there were numerous shallow marshes in the 1950s, many of which dried up by late summer. Most of these marshes are now drained. While there are no bedrock outcrops in the Red River Valley region, cobble deposits in beach ridges in the eastern part of the lobe were sources of toolstone. These deposits are most easily accessible where rivers cut through the beaches.
After the final retreat of Lake Agassiz from this lobe about 8200 B.C., the land was covered by tallgrass prairie. River bottom forests (elm, ash, and cottonwood) were present along the Red River and its major tributaries, and an irregular band of aspen-oak forest or aspen parkland spread along the lobe’s northeastern edge. Like a rainbow, the aspen band arced across the northern prairie in Canada and extended southward toward the Rocky Mountains. The major Late Holocene food resource was bison, which were present along the Red River in large herds (Figure 1.5c). Large elk herds were also reported in the early 1800s. Near the eastern edge of the region, deer were available, while in the northeast, moose and even woodland caribou were present. Some fish and mussels were available in the Red River and its major tributaries. Waterfowl were seasonally abundant on the shallow marshes, and plant foods would have included prairie species, such as prairie turnip, marsh plants like cattails, berries, and nuts from the riparian forests.
Today, the long eastern (or Beltrami) arm of glacial Lake Agassiz is appropriately called the Big Bog, for it is covered by vast wetlands and patterned bogs (tree-covered islands of vegetation) (Figure 1.5d). The Big Bog is a fairly recent development. Following the retreat of Lake Agassiz about 11,200 B.C., wet prairie and patches of aspen and oak woodlands covered the area. About 2500 B.C., in response to a cooler, wetter climate, extensive peatlands began to build up over most of the eastern two-thirds of the Big Bog region. They followed a developmental progression from cattail marshes, to sedge meadows and heath bogs, to sphagnum moss. Bog conifers, such as spruce, tamarack, cedar, and balsam, grew on higher ground. This large and sparsely occupied area of the state remained a watery barrier between the Headwaters Lakes area of the Mississippi River to the south and Canada for thousands of years.
The Big Bog region of northwestern Minnesota contains Lake of the Woods County and parts of Beltrami, Clearwater, Koochiching, Marshall, Pennington, Polk, Red Lake, and Roseau counties. Although six to eight feet of lake sediment and up to 100 feet of glacial drift cover most of the bedrock, outcrops of Precambrian bedrock occur around Lake of the Woods, along the Rainy River, and in eastern Koochiching County. Lakes and transecting rivers are rare in the heart of the Big Bog, but lakes and streams are present around its borders. Several large, shallow remnants of Lake Agassiz (Red, Thief, and Mud lakes) are on its western edge and its southwestern corner is drained by the headwaters of rivers that flow west to the Red River (Figure 1.5e). Figure 1.5e is a picture of Thief Lake. North-flowing rivers, which intersect the west-flowing Rainy River along the northern edge of the region, include the Roseau, Warroad, Rapid, Little Fork, and Big Fork (Figure 1.5f). Late Holocene game animals included deer, moose, caribou, beaver, and black bear. Some bison were present in the west. Fish were plentiful in Red Lake, Lake of the Woods, and the major rivers, and waterfowl were seasonally abundant. Wild rice was present in the region, too, though it was not as abundant as in the central lakes regions to the south.
Northeastern Minnesota
Northeastern Minnesota is the most rugged part of the state, with the state’s highest (2,301 feet above sea level) and lowest (602 feet above sea level) elevations (Figure 1.6). Its rocky and ice-scoured surface is a result of a complicated glacial history in which erosion rather than deposition was a dominant process. As a consequence, drift is relatively thin or absent over wide-areas and lakes pool in bedrock cavities, unlike the state’s southern and western lakes, which are embedded in drift. Because of different bottom profiles and water chemistries, the fish species in the two sets of lakes are different and large stands of wild rice are not common in northeastern lakes. The resource zone’s Late Holocene vegetation was dominated by pine and spruce, with some inclusions of aspen and birch (Figure 1.6, Figure 1.6a). The figures show glimpses of a spruce forest and a white pine forest, respectively. Game animals included deer, moose, caribou, beaver, and bear (Figure 1.6b, Figure 1.6c). Waterfowl were seasonally abundant, especially on interior lakes.
Like northwestern Minnesota, this large-scale resource zone is divided into two distinctive parts, an interior Border Lakes region and a Lake Superior region. The Border Lakes region is famous for its interconnected complex of tightly packed lakes and rivers (Figure 1.6e). Figure 1.6e is a picture of Sea Gull River. The Pigeon River drains rivers in the eastern part and the Rainy River those in the central and western parts. The region covers northern Cook, Lake, and St. Louis counties, and the small portion of eastern Koochiching County that includes Nett Lake and the eastern area of Rainy Lake. It also extends northward into Ontario where Quetico Provincial Park is today. High quality toolstone outcrops at locations associated with Gunflint and Vermilion iron formations.
The eastern Lake Superior region stretches along Lake Superior. It includes the eastern edges of Carlton, Cook, Lake, and St. Louis counties, and extends northward along Lake Superior into Ontario as far as Thunder Bay. Unlike other regions of Minnesota, the Lake Superior shore has rocky cliffs with many small bays and points. Abundant Precambrian bedrock exposures are present, making waterfalls common as the short, steep streams and rivers cascade down the 900 to 1500 foot drop to Lake Superior. In contrast, the southern tip of the region is the flat plain of glacial Lake Duluth, which is drained by the St. Louis and Nemadji rivers. Lakes are rare in the Lake Superior shore highlands, though brown trout lived in the major streams below cataracts and large fish populations were present in Lake Superior. Game animals were less common than in the Border Lakes region.
Central Minnesota
The state’s largest resource zone, Central Minnesota is covered by extensive wetlands, many deep lakes (some reaching depths of more than 95 feet), and gently rolling hills. The topography of the zone is a patchwork of hilly moraines, and till, outwash, and glacial lake plains, another legacy of the Wisconsin glaciation. The tops of the most prominent of the moraines, the Alexandria Moraine and Itasca Moraine, are about 902 feet (275 m check) above the bed of glacial Lake Agassiz to the north. Only the plain of glacial Lakes Upham-Aitkin lacks lakes. In some areas glacial sediment is 490 feet thick. Large lakes include Bemidji, Leech, and Mille Lacs, one of the state’s largest lakes. Wild rice beds were extensive throughout most of Central Minnesota, and fish and waterfowl were abundant in its many lakes and rivers.
This resource zone, too, can be usefully divided into two regions based on differences in vegetation and watersheds. A more northern Coniferous Lakes region includes portions of Aitkin, Beltrami, Carlton, Cass, Clearwater, Crow Wing, Hubbard, Itasca, Kanabec, Koochiching, Lake, and St. Louis counties. The Coniferous Lakes region incorporates much of what has been called the Headwaters Lakes district of Minnesota, for the Mississippi River crosses much of the area, flowing through or near several large lakes as it leaves its source in southeastern Clearwater County (Figure 1.7, Figure 1.7a, Figure 1.7b). The figures show various phases of the river as it pasts through the region. The path of the Mississippi has changed significantly over the last 15,000 years, though by the beginning of the Late Holocene period (about 2500 B.C.) it began to follow what is essentially its modern route. The western part of the region is drained by rivers flowing into the Red River, while the northeast part is drained by the St. Louis River, which flows into Lake Superior. The southeast is drained by rivers flowing into the St. Croix River and eventually the Mississippi. Precambrian outcrops are found in the northeast, along with taconite deposits that contain some high quality toolstone, in particular cherts, jasper, and taconite.
Pine trees (white, jack, and red) dominated the Late Holocene vegetation of the Coniferous Lakes region, though there were significant inclusions of deciduous trees (elm, maple, basswood, ash, oak, aspen, and birch). Figure 1.7c shows an area of aspen parkland. Peat bog vegetation covers the glacial lake plains in the southeast portion. Late Holocene game animals included deer, beaver, moose, and black bear.
The more southern Deciduous Lakes region includes most of central and east central Minnesota, including Anoka, Benton, Cass, Chisago, Crow Wing, Hennepin, Isanti, Mille Lacs, Morrison, Ramsey, Sherburne, Stearns, Todd, Wadena, Washington, and Wright counties, and parts of Becker, Dakota, Douglas, Kandiyohi, Kanabec, Meeker, Otter Tail, Pine, Pope, and Swift counties. The region could be extended eastward into west central Wisconsin. The Mississippi-Sauk River flows through the eastern and central parts of the region, and the Lower St. Croix River forms the eastern boundary (Figure 1.7d, Figure 1.7e). The figures show the Mississippi River bottoms (Figure 1.7d) and the St. Croix River (Figure 1.7e) as they pass through the region. Other important waterways include the Crow, Rum, and Snake rivers. Streams flowing west into the Red River drain the western part. Bedrock outcrops are limited to occasional granite rock exposures in the center and eastern edge of the area.
In the 1850s the vegetation in the southern and westerns parts of the Deciduous Lakes region was dominated by Big Woods species (elm, maple, and basswood) with many large incursions of prairie and oak woods. Since the development of extensive Big Woods forests was a recent event (after A.D. 1500), much of the Big Woods area was probably oak forest during the Late Holocene. Oak forest was still dominant in the eastern portion of the region in the 1850s. A mixed deciduous-coniferous forest dominated by pine was present in the northern sector. Late Holocene game animals included deer throughout the region, small herds of bison and elk in the south and west, and beaver, black bear, and even moose in the north and east.
Southwestern Minnesota
Thick ice age deposits of sand, gravel, and clay also cover southwestern Minnesota. The Coteau des Prairies (Buffalo Ridge), an elongated block of bedrock, dominates the resource zone’s topography. The plateau stretches westward into eastern South Dakota, where it reaches an elevation of more than 2,100 feet. Two prominent belts of high, hilly terrain on its eastern flank are late-glacial moraines. The outermost belt, the Bemis Moraine, forms the high crest of the plateau and is an impressive topographic barrier in this corner of the state. Southwest of the moraine is a lake-free, gently rolling surface of drift not covered by late surges of the Wisconsin glacier. These different surface histories divide the section into two distinct regions, a Southwest Riverine and a Prairie Lake.
Located in the extreme southwestern corner of Minnesota, the Southwest Riverine region includes all of Rock County, large parts of Pipestone and Nobles counties, and small portions of Lincoln and Murray counties. Although Minnesota’s smallest region, it is part of a larger, well drained out-state topographic unit that includes parts of northwestern Iowa and southeastern South Dakota. Rock River, which flows south to connect with the Missouri River system, is the region’s major drainage-way. Many small but deeply entrenched creeks, such as Split Rock and Pipestone, flow to the southwest. While bedrock outcrops of Sioux Quartzite are common in the western part of the region, there are no outcrops of toolstone of good flaking quality. Concentrated exposures of catlinite, a soft, clay-rich stone produced from chemically weathered quartzite, were mined by native Minnesotans to make pipes, plaques, and other items. Although not glaciated by Late Wisconsin ice surges, extensive loess deposits caused by late glacial winds cover earlier glacial till.
Before farming changed the land’s surface, the Southwest Riverine region was covered by tallgrass prairie. Trees were scarce due to regular prairie fires and occasional droughts, though some woody vegetation was present along the major streams and at favorable topographic breaks. The largest woods were river bottom forests dominated by elm, ash, and cottonwood along the Rock River in south central Rock County. Major game animals included bison, elk, and smaller upland mammals. The only common game bird in the Late Holocene may have been sharp-tailed grouse, for waterfowl were not abundant due to the absence of lakes and multiple large rivers. Seasonally available plants included the prairie turnip (Psoralea esculenta) and ground plum (Astragalus caryocarpus).
The much larger Prairie Lake region covers most of southwestern and south central Minnesota. It includes all of Big Stone, Blue Earth, Brown, Carver, Chippewa, Cottonwood, Faribault, Freeborn, Jackson, Lac Qui Parle, Le Sueur, Lyon, McLeod, Martin, Nicollet, Redwood, Renville, Scott, Sibley, Stevens, Swift, Watonwan, and Yellow Medicine counties and parts of Douglas, Grant, Kandiyohi, Lincoln, Meeker, Nobles, Otter Tail, Pipestone, Pope, Rice, Steele, Traverse, and Waseca counties. The region extends into northeastern South Dakota and north central Iowa.
The interior topography of the Prairie Lake region is the typical swell and swale topography of a ground moraine. Hilly end moraines are found along its northern, eastern, and southern edges. The major topographic features are the broad valley of the Minnesota River, which bisects the area southwest to northeast (Figure 1.8), and the scarp of the Coteau des Prairies highland in the west. The Minnesota River valley was the main channel of glacial River Warren, which intermittently drained glacial Lake Agassiz. Prairie “pot-hole” lakes are numerous and vary greatly in size (Figure 1.8a). All of the lakes are shallow, with none exceeding 30 feet in depth. During severe droughts, most of these shallow lakes dry up (Figure 1.8b, Figure 1.8c). Besides losing their aquatic plants and animals, dry lakes are ineffective firebreaks. Many streams and rivers crisscross this part of southwestern Minnesota. Many of the larger rivers, such as the Minnesota, Redwood, Cottonwood, and Des Moines, follow the path of earlier glacial meltwater channels. All of these streams and rivers eventually flow into the Mississippi River.
Bedrock outcrops are rare in the Prairie Lake region, especially deposits of good-quality toolstone. In the eastern section, occasional outcrops of Paleozoic rocks near the confluence of the Blue Earth and Minnesota rivers include some deposits of high quality chert. In the western section, there are numerous outcrops of Sioux Quartzite in Cottonwood County. Granites and poorly consolidated Cretaceous rocks, such as shale, are found in the Minnesota Valley.
During the precontact portion of the Late Holocene period (c. 2500 B.C. to 1650), the Prairie Lake region was covered with tallgrass prairie (Figure 1.8d, Figure 1.8e). Trees were uncommon in the western section. Exceptions were narrow river-bottom forests and oak woods along the major river valleys and small patches of woodland in fire-protected areas (peninsulas, islands, and isthmuses) at major lakes. The Minnesota River valley contained the principal wood resources for the western part of the region. The eastern part contained extensive Big Woods vegetation (elm, maple, and basswood) (Figure 1.8f, Figure 1.8f) in the north and patchy oak parkland with large prairie openings that became more numerous to the west in the south (Figure 1.8g). While the modern prairie-forest border was established about 2,500 years ago, the southern bulge of Big Woods vegetation is a recent phenomenon, as mentioned earlier. Oak woodlands were present all along the eastern edge of the Prairie Lake region until about 300 years ago.
Bison and an occasional large elk herd were the dominant upland game animals in the Prairie Lake region during the Late Holocene (Figure 1.8h). White-tailed deer were present along the Minnesota River valley and in the eastern woodland fringe. The major animal-food differences between the two southwestern Minnesota regions are a result of the many shallow lakes in the Prairie Lakes region and their absence in the Southwest Riverine region. The southwestern lakes contained extensive populations of aquatic mammals, such as muskrats, and waterfowl and fish, as well as edible plants like water lilies and cattails. Though not extensive, wild rice was present, especially in the Minnesota River valley and in a few northern and eastern lakes. Upland plant resources included the prairie turnip, ground plum, and acorns in the oak woods.
Southeastern Minnesota
The Southeastern region of Minnesota has a stream-dissected terrain that was not glaciated during the Late Wisconsin Ice Age. Although ice free, the resource zone was covered by a deep deposit of loess, a powdery silt deposited by wind during the last glaciation. The deep erosion of the loess resulting from rivers flowing into the Mississippi River left a lake-free land surface with deeply entrenched flat-floored stream valleys and numerous bedrock exposures that contain high-quality toolstone. While no natural lakes are in its interior, valley bottom lakes are present along the Mississippi River. Some like Lake Pepin, which stretches from Red Wing to Wabasha, are quite large (Figure 1.9a). Three major river systems, the Cannon, Zumbro, and Root, extend westward from the Mississippi into the region’s interior. Figure 1.9b is a picture of the smaller Yucatan valley.The wide Mississippi River valley, which is bordered by steep, scenic bedrock walls, is itself a complex of interconnected stream channels (Figure 1.9c). Southeastern Minnesota includes Dodge, Fillmore, Goodhue, Mower, Olmsted, Wabasha, and Winona counties, and parts of Dakota, Freeborn, Rice, and Waseca counties. The resource zone/region continues into adjacent corners of Wisconsin and Iowa.
During the Late Holocene, forests of elm, ash, and cottonwood lined the river lowlands, and Big Woods forests of maple, elm, and basswood occupied the uplands near the Mississippi River. Patches of oak groves in the prairie, often described as “oak barrens,” were scattered across the western part of the region (Figure 1.9d, Figure 1.9e), while the middle of the region was a more open prairie. Subsistence resources included deer, elk, and scattered bison in the uplands and mussels, fish, and waterfowl in the rich bottomlands (Figure 1.9f). Edible plants would have included water lilies and other aquatic flora, and upland plants like the prairie turnip. Extensive oak woods were a rich source of acorns. The region’s favorable climate and extensive bottomlands made it more suited for precontact corn (maize) horticulture than any other region in the state.
Minnesota’s Climate and Weather
When residents of Florida or Arizona think of Minnesota, blizzards and long, snowy, cold winters spring to mind. Like its lakes and streams, and transitional plant and animal communities, Minnesota’s climate and weather are intimate parts of its character. The state’s climate, which is characterized by warm, humid summers, cold, dry winters, and a steep south-north temperature gradient, is determined by its geographical location near the center of North America, its long, narrow shape, and the coming together of three air masses over its surface. Cool, dry air flows in from the northwest, relatively dry, warmer air from the west, and humid, warm air from the south. When the air masses clash, the result is moister in the form of rain or snow, tornados, and sudden temperature inversions.
Although Minnesota’s climate can be regionally variable, average temperatures increase from northeast to southwest and average precipitation increases from northwest to southeast (Figure 1.10). The frost-free growing season ranges from 140 to 160 days in the south to less than 120 days in the north, with a gradient in between (in a normal year, the average temperature is 2o to 3o Fahrenheit cooler for every 100 miles of northward travel). Northern lakes like Lake of the Woods and the border lakes tend to freeze over in mid- to late November and to be ice-free by late April. Even Lake Superior occasionally freezes over in very cold winters. Southwestern lakes freeze over by early December and are ice-free by early April. All of this is very important information if you planned to travel by canoe or grow corn during the warmer months in precontact Minnesota. For precontact farmers, the growing season in the northern two-thirds of the state was probably too short to grow the varieties of corn and beans then available as dependable crops. Superimposed on this pattern of climate are seasonal floods, thunderstorms, and tornados. Floods occur along the larger southern rivers about one to two years out of ten.
Although a welter of seemingly dull facts and figures, the pattern of temperature and moister in the state determined the pre-1850s distribution of plant and animal communities in the state, and these distributions affected the distribution of precontact Late Holocene Native lifeways, as we will demonstrate throughout this book. Said another way, to understand the distribution of precontact Late Holocene Native lifeways, we must become knowledgeable about the physical world these early Minnesotans lived in.
Contributors to this chapter: Scott Anfinson and Guy Gibbon
Date of last contribution: December 2008