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Resource Management System Background III Natural History and Landscape The City of Lino Lakes is located within the Anoka Sandplain ecological subsection of central Minnesota. The Anoka Sandplain is a 1,875 square mile glacial outwash plain that includes portions of 13 Minnesota counties, and is centered on most of Anoka, Isanti, and Sherburne counties. The Anoka Sandplain was created and shaped by the last major glacial episode in Minnesota — the Wisconsin glaciation — between 35,000 and 10,000 years ago. The City of Lino Lakes is located within the historic lake bottom of Glacial Lake Fridley which formed from glacial ice -melt water circa 12,000 years ago. The release of glacial melt water from Glacial Lake Fridley created deep, broad, irregular troughs within the glacial lake bottom. These troughs formed the Rice Creek Chain of Lakes and associated wetland complexes of present day, as well as numerous other lake chains to the northwest and southeast of Lino Lakes. The glacial history of Lino Lakes resulted in complex patterns of surficial geology, hydrology, and soil associations that remain as important influences on development, agricultural patterns, and natural resources conservation opportunities within the city. The upland soils of Lino Lakes are typically sandy, moderately to well drained, and nutrient poor. Wetland soils are typically shallow to deep organic peat deposits over sand or saturated sands, which occur within complex networks of braided depressions throughout the city's landscape. The southeastern most edge of the city includes a small portion of a glacial till. The upland and wetland soils of this landscape inclusion are comprised of fine - textured silt loams, barns, and clays that are poorly drained. Topography throughout the city is generally flat to slightly undulating, and the regional groundwater table is typically shallow below the soil surface. Presettlement Vegetation (circa 1850) Native vegetation patterns of Lino Lakes were described at the time of Minnesota's Original Land Survey (circa 1850), and prior to European settlement of Minnesota. Native vegetation communities within the City prior to European settlement were primarily comprised of oak barrens and savannas, aspen /oak forests and woodlands, dry, mesic, and wet prairies, rich fens, poor fens, bogs, tamarack swamps, a network of shallow lakes and associated marshes, and inclusions of mesic hardwood forest (Figure 2 -1). Large -scale natural processes dramatically influenced the formation, establishment, and succession of natural vegetation patterns and natural communities within the landscape over thousands of years prior to European settlement. These natural processes include: surface and sub - surface hydrology, flooding, drought, herbivory, wildlife migration, plant dispersal, plant community succession, and occasional to frequent wildfires. Over the past 150 years, the natural landscape and associated landscape processes have been widely altered to accommodate agricultural land uses, development, and other anthropocentric uses of the landscape. • •