Soil Orders and Regions of Missouri
Seven of the Twelve soil orders can be found in Missouri:
Alfisols
Receive their name from the weathering of the Iron (Fe)
and Aluminum (Al) out of the mineral structure. Alfisols
are mature soils that are formed in humid climates with
a downward movement of clayand and contain a slightly
acidic subsoil compared to the acidic Ultisols. Alfisols
are typically found in forested conditions containing
either hardwood or deciduous trees.
Photo Courtesy of MCSS
Ultisols
Are soils that formed under forest conditions in humid climates.
The forests can be a mix of hardwood and coniferous trees, but
typically the soil is acidic and is mostly coniferous. Ultisols
contain a greater amount of iron and aluminum in the soil than
Alfisols. Utlisols are found mostly in the Southeasten United
States in Georgia and Alabama.
Photo Courtesy of MCSS
Mollisols
Are softer soils due to the high amount of organic content.
Mollisols are slightly acidic, contain good structure with
a deep, thick, dark surface that is good for crop production.
Mollisols are formed under native prairies and some poorly
drained areas.
Photo Courtesy of MCSS
Inceptisols and Entisols
Inceptisols- Are soils that are more developed than
Entisols, but are formed under forests.T his soil ranges
from low to high in natural fertility, and is used in
the production of crops, forest, and range land
Photo Courtesy of MCSS
Entisols- Are soils that are young or recent and have
very little horizonation. They are typically found in flood
plains and around cities due to their productivity for
agriculture and access to water. Entisols are also formed
under forests with the constant recharge of organic matter.
Photo Courtesy of MCSS
Vertisols
Are clay soils with high shrink and swell potential. The soils
have distinct wet and dry periods throughout the year, with
deep cracks forming during the dry period. Vertisols develop
from limestone, basalt, or other calcium and manesium rich
parent materials. Vertisols are found in subhumid to semi-
arid climates, and the most common vegetation is a grassland.
Vertisols occur in areas where the climate consists of several
months of dry periods, which causes the clay to shrink and create
deep, wide cracks. When precipitation occurs, the water enters the
cracks causing the clay to swell. Because of the shrink and swell
properties of Vertisols, road and building construction is
extremely difficult.
Vertisols have been called 24-hour soils due to being too wet to
plow one day and too dry the next. Vertisols have a high natural
fertility, and the major land uses are for wetlands, crops, and
range land.
Photo Courtesy of MCSS
Histosols
Are organic soils fromed from materials high in organic content.
Histosols are found in wetlands from the equator to the arctic regions.
The organic deposits accumulate in marshes, swamps, and bogs
from water loving plants like pond-weed and cattails.
Histosols range in color from black to dark brown, and have a high
water-holding capacity. Histosols are better known as peat and found
mostly in the glaciated areas of Wisconsin, Michigan, Minnesota,
and New York.
More than 50% of all wetlands in the U.S. have been drained for
agricultural use. An example of drained wetlands in Missouri is the
bootheel region in Southeast Missouri. This soil ranges from moderate
to high in soil fertility, and the major land use is in wetlands and crops.
Photo Courtesy of NRCS
The Five Soil Orders Found Outside of Missouri are:
Andisols
Are developed from volcanic activity and have low load bearing capacity,
think of Jell-O, and slumps easily. Phosphorous is not available to plants
due to the strong hold of Andisols on phosphorous. The major land uses
being tundra, forest, and range land with moderate natural fertility.
Photo Courtesy of NRCS
Aridsols
Are found in arid climates, warm and cool, but in the United States
Aridsols are found in the Southwest through Western Montana and into
Canada. Aridsols can have high native fertility, but also contain
soluable components like carbonates, gypsum, and salts. Decent water
quality and quantity is hard to come by due to dissolved salts and lack
of precipitation.
Photo Courtesy of NRCS
Gelisols
Contain permafrost within the upper 78 inches of the soil.
Gelisols are known for the stability management issues and
patterned ground formations that are created due to the freeze
and thaw climate. The major land uses are bogs and tundra
with moderate fertility.
Photo Courtesy of NRCS
Oxisols
Are very old and highly weathered soils that are found in Central and South
America. Oxisols contain large amounts of iron and aluminum oxides
in the soil. Oxisols are found in tropical climates with the major land uses being
forests and crops, but the soil contains low natural fertility. Slash and burn
agriculture is practiced to add the needed nutrients to the soil so the land can be
used to sustain agriculture.
Photo Courtesy of NRCS
Spodosols
Contain accumulations of organic matter mixed with aluminum and iron oxides
creating sandy, acidic soil. Spodosols are found monstly in cool humid or
temperate climates,and are low in natural fertility with the major land
use being coniferous forests. Spodosols can be used for agricultural purposes
in the cultivation of potatos, blueberries, and acidic woody ornamental trees.
Photo Courtesy of NRCS
Missouri map (Click here to view Missouri map of dominant soil orders.)
