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| The photo above
shows a Colton soil developed in a glacial outwash landform |
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A portion of a high intensity soil survey map. This
hillside was formerly covered by the sea during deglaciation.
Elevations above 220 feet are mantled by thin and discontinuous
glacial beach deposits interbedded with glacial tills
(Peru soils); downslope are finer grained dense basal
tills (Howland soils); the lowland at the toe-slope contains
thick deposits of marine silty clay sediments (Scantic
and Lamoine soils). A complex area of bedrock outcrop
and very shallow to moderately deep (less than 40 inches
to bedrock) soils is mapped as Thorndike-Abram channery
loam-Rock outcrop.
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The
thin veneer of unconsolidated sediment overlying Maine’s
bedrock was deposited beneath and at the terminus of the Laurentide
ice sheet 11,000 to 15,000 years before present. These heterogeneous
sediments are collectively called “parent material”.
There are 5 broad classes of parent materials in Maine: sand
and gravel deposits, loose ablation till, dense basal till, marine/lake
silty clay sediments, and peat (organic) deposits. In the upper
part of these parent materials, soils have slowly formed since
deglaciation. Efficient use and management of Maine’s soils
arises from the careful study, description, and mapping of land
areas. Agricultural products, drinking water supplies, timber
resources, road construction activities, waste water disposal,
pollution mitigation, building sites, town planning, recreation
areas, conservation lands, and untold other intricacies of life
are directly linked to proper utilization of Maine’s
varied soils.
To this end, I can provide soil surveys tailored to properly
address a client’s land use and management objectives.
Different levels of soil map intensities can match particular
land use objectives. For example, the U.S.D.A. Natural Resources
Conservation Service county soil maps were developed at scales
of 1:15,840 (1 map inch = 1,320 ft. on the ground) or smaller
scale. High intensity soil surveys, utilizing mapping scales
of 1 map inch = 200 ft. on the ground, and up to 1 in. = 50 ft.,
can provide the detail needed for intensive land uses such as
building construction, stormwater design, erosion and sediment
control planning, natural resource protection, and other uses.
Integral to, and accompanying the high intensity soil map, is
a report containing the soil pit logs and descriptions of soil
map units which explain specific properties and limitations of
each soil - texture, coarse fragments, drainage class (depth
to seasonal high water table), restrictive layers, parent material,
hydrologic group, slope, geomorphology, surface stoniness, and
depth to bedrock. Soil test pits are dug by backhoe or excavator
and allow for full soil descriptions down to 60 inches below
ground surface.
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The terminus
of the Greenland ice sheet. An analogous climate, flora,
and fauna existed in Maine during deglaciation. Subglacial
sediment is dumped at the terminus where it is water-sorted,
forming a broad sand and gravel outwash plain. Maine’s
river valleys and vast blueberry barrens formed in this
manner.
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Approximately
50% of the landmass of the conterminous U.S. is dedicated
to agricultural production. The photo shows an Ap horizon
(black top soil) 24 inches thick developed in glacially
windblown sand. These soils represent the highest and best
fertility agricultural lands in New England. With proper
use and management, they can sustainably produce high crop
yields indefinitely. |
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Approximately
24% of Maine is wetland. These lands serve vital purposes
such as water filtration for subsurface aquifers, flood
control, pollution control such as nitrogen and phosphorus
absorption, habitat for ecologically diverse wildlife and
fisheries, sedimentation control, and a host of other functions.
The photo shows a typical hydric soil morphology of a thick
organic horizon underlain by a chemically reduced iron
and manganese (gleyed) mineral soil horizon. |
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