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<br />BACKGROUND
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<br />This chapter summarizes background information helpful for understanding the natural
<br />environment of Lino Lakes. The historic ecological patterns and vegetation communities found
<br />in the city were those that were adaptable to the local soil conditions, hydrologic patterns, and
<br />climate. Now, both remnants of these historic systems and communities of introduced species
<br />e.g., agricultural species, lawns, orchards, and prairies to wetlands and lake edges have all been
<br />historically present in the city. Clearly, the natural character of the city remains one of its most
<br />important aspects and essential to the sense of place found here.
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<br />Natural History and Landscape
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<br />Lino Lakes is located within the Anoka Sandplain ecological subsection of central Minnesota.
<br />The Anoka Sandplain is a 1,875 square mile glacial outwash plain that includes portions of 13
<br />Minnesota counties, and includes most of Anoka, Isanti, and Sherburne counties. The Anoka
<br />Sandplain was created and shaped by the last major glacial episode in Minnesota – the
<br />Wisconsin glaciation – between 35,000 and 10,000 years ago.
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<br />Lino Lakes is located within the historic lake bottom of Glacial Lake Fridley which formed from
<br />glacial ice-melt water circa 12,000 years ago. The release of glacial melt water from Glacial
<br />Lake Fridley created deep, broad, irregular troughs within the glacial lake bottom. These troughs
<br />formed the Rice Creek Chain of Lakes and associated wetland complexes of present day, as well
<br />as numerous other lake chains to the northwest and southeast of Lino Lakes.
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<br />The glacial history of Lino Lakes resulted in complex patterns of surficial geology, hydrology,
<br />and soil associations that remain as important influences on development, agricultural patterns
<br />and natural resources conservation opportunities within the city. The upland soils of Lino Lakes
<br />are typically sandy, moderately to well drained, and nutrient poor. Wetland soils are typically
<br />shallow to deep organic peat deposits over sand or saturated sands, which occur within complex
<br />networks of braided depressions throughout the city’s landscape. The southeastern most edge of
<br />the city includes a small portion of a glacial till. The upland and wetland soils of this landscape
<br />inclusion are comprised of fine-textured silt loams, loams, and clays that are poorly drained.
<br />Topography throughout the city is generally flat to slightly undulating, and the regional
<br />groundwater table is typically shallow below the soil surface.
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<br />Native vegetation patterns of Lino Lakes were described at the time of Minnesota’s Original
<br />Land Survey (circa 1850), and prior to European settlement of Minnesota. Native vegetation
<br />communities within the city prior to European settlement were primarily comprised of oak
<br />barrens and savannas, aspen/oak forests and woodlands, dry, mesic, and wet prairies, rich fens,
<br />poor fens, bogs, tamarack swamps, a network of shallow lakes and associated marshes, and
<br />inclusions of mesic hardwood forest.(See Figure 2-1, Presettlement Vegetation.) Large-scale
<br />natural processes dramatically influenced the formation, establishment, and succession of natural
<br />vegetation patterns and natural communities within the landscape over thousands of years prior
<br />to European settlement. These natural processes include: surface and sub-surface hydrology,
<br />flooding, drought, herbivory, wildlife migration, plant dispersal, plant community succession,
<br />and occasional to frequent wildfires. Over the past 150 years, the natural landscape and
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