Geological History of the Landscape
Rice County Minnesota is situated in the southeastern region of the state. The county spans 495 square miles (316,800 acres) and its highest land, 1300 feet above sea level, lies in the southeastern part of the county. Rice's lowest land, 900 feet above sea level, can be found in the Cannon River Valley (Leverett and Sardeson 1919). The landscape is the direct result of prehistoric geological forces. During the early Paleozoic, great inland seas covered all of southeastern Minnesota. This giant body of water, which changed its border over a span of 200 million years, left behind sediments that eventually became the bedrock that formed the base of southeastern Minnesota. In last 20,000 years, two different glaciers covered the land (Ojakangas and Matsch 1982).
Superior Lobe 35,000 years BP? Rice County Geological
Relief Map 1884 DesMoines Lobe 13,000 years BP
Click Image!
Click Image!
Click Image!
(Bray 1977)
(Winchell 1900)
(Bray 1977)
The Superior Lobe came first, creating the St. Croix Moraine
with sediment from the Lake Superior region, followed by the Des Moines Lobe.
Southeastern Minnesota’s present physical landscape emerged as the result
of The Des Moines Lobe’s retreat, only 13,000 years ago. This last glacier
made Minnesota a penneplain, removing weathered rock, detritus, and further
leveling the land by filling in low areas with glacial deposits. The Des Moines
Lobe also distributed limestone and shale-rich drift across the state (Ojakangas
and Matsch 1982). There are 4 geomorphic regions in Rice County. Three
of the regions resulted from the growth and retreat of the Des Moines, the
fourth from earlier glaciations. Flat to rolling till plains formed
on the eastern edge of the Des Moines, flat-topped circular hills from poorly
formed Des Moines drainage networks, sediment streams from well formed Des
Moines drainage networks, and finally older dissected landscape of loess covering
old glacial till. (USDA 2000). Such glacial deposits compose the base for
Rice County's soil.
Rice county is an area with excellent water resources. The county has 21 square miles of lakes (9,400 acres), and 82% of the Rice's area is drained by the Cannon River, northeastward to the Mississippi at Red Wing. The southeastern part of the county is drained the Zumbro River eastward and the norwestern part is drained toward the north by the Minnesota River. The water supply in Rice County is directly related to the thickness of the mantle of glacial drift left by the Des Moines glacial lobe. (USDA 1975). Numerous streams and rivers criss-cross the county and connect many of the lakes, which are found mostly in the western half. Water played an important role in the development of Rice's County's economy.
Click Images for a closer look!
Source: MN DNR Data Deli
After the retreat of the ice, mollisoils and alfisoils
began to form under the growing prairie and forestland respectively (Grimm
1984). These soils form a continuum across the area, constituting prairie,
prairie-woodland, and woodland soils. In the mid-Holocene, much of the prairie
was Big Woods forest biome dominated by elm, basswood, sugar maple, and hop
hornbeam. Pollen evidence suggests that tallgrass prairie preceded the
characteristic trees of the Big Woods. These trees may have reached certain
areas of southern Minnesota only several decades before 1850. By the mid-19th
Century, tallgrass prairie and Big
Woods forest biomes dominated the county. The fluxing border
between these environments was directly influenced by fire before and during
the time of settlement. With the prairie's rich soil on one side
and the forest on the other, the border area between these two biomes was
an appealing spot for early settlers wanting both lumber and fertile
soil near their homestead location..
Rice County Presettlement Vegetation
Click Image for a closer look!
Source: MN DNR Data Deli
For more information on southeastern Minnesota environments of the
1800s, click on the articles below!
The Effects of Fire on the Prairie/Forest
Border in Southern Minnesota by Erin Withers
Southeastern Minnesota’s Prairiescape: A Product of a Dynamic Past by Natalie Patch
Upon their arrival in Rice County, the settlers witnessed a landscape of distinct and uncultivated biomes. Tall grass prairie dominated the southeastern corner of the county and blended into the Big Woods in the northwestern part of the county. The resulting border between these two biomes constituted a unique environment as well. Alexander Faribault, a French fur trader, first settled in the area of present-day Rice County in 1826; the county itself wasn't organzed until 1855. Moderate climate, abundant water, and fertile soil made Rice County an excellent location for agriculture. To learn more about early settlers and how the landscape affected their lives, check out the Economic and Ethnicity pages in this report on Rice County. To read first hand accounts of mid- to late-nineteenth century farming life in Rice County click here.
Beginnings
of Faribault, 1862 Minnesota
Praire Barn, 1880
Source: Minnesota Historical Soceity