_PERMIT FILE - M2000052

• Permit No: M2000052
• IBM Index Class Name: Permit File
• Doc Name: MAPS & EXHIBITS
• Media Type: D
• Archive: No

U.S. DEPARTMENT OF AGRICULTURE PAGE 4 OF 5
NATURAL RESOURCES CONSERVATION SERVICE 01/18/00
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PHYSICAL PROPERTIES OF SOILS
Endnote -- PHYSICAL PROPERTIES OF SOILS--Continued
ORGANIC MATTER is the plant and animal residue in the soil at various stages of decomposition. In report ,I,
the estimated content of organic matter is expressed as a percentage, by weight, of the soil material that is
less than 2 millimeters in diameter. The content of organic matter in a soil can be maintained or increased by
returning crop residue to the soil. Organic matter affects the available avatar capacity, infiltration rate, and
tilth. It is a source of nitrogen and other nutrients for crops.
EROSION FACTOR K indicates the susceptibility of the whole soil (including rocks and rock fragments) to
sheet and rill erosion by water. Factor K is one of six factors used in the Universal Sail Loss Equation (USLE)
to predict the average annual rate of soil loss by sheet and rill erosion in tons per acre per year. The
estimates are based primarily on percentage of silt, sand, and organic matter (up to 4 percent) and on soil
structure and permeability. Values of K range from 0.05 to 0.69. The higher the value, the more susceptible
the soil is to sheet and rill erosion by water.
EROSION FACTOR Kf is like EROSION FACTOR K but it is for the fine-earth fraction of the soil. Rocks and
rock fragments are not considered.
EROSION FACTOR T is an estimate of the maximum average annual rate of soil erosion by wind or water that can
occur without affecting crop productivity over a sustained period. The rate is in tons per acre per year.
isERODISILITY GROUPS are made up of soils that have similar properties affecting their resistance to wind
erosion in cultivated areas. The groups indicate the susceptibility of soil to wind erosion. Soils are grouped
according to the following distinctions:
1. Coarse sands, sands, fine sands, and very fine sands.
These soils are generally not suitable for crops. They are
extremely erodible, and vegetation is difficult to
establish.
2. Loamy coarse sands, loamy sands, loamy fine sands, loamy
very fine sands, and sapric soil material. These soils are
very highly erodible. Crops can be grown if intensive
measures to control wind erosion are used.
3. Coarse sandy looms, sandy looms, fine sandy looms, and
very fine sandy looms. These soils are highly erodible. ,
Crops can be grown if intensive measures to control wind
erosion are used.
4L. Calcareous lows, silt looms, clay looms, and silty clay
looms. These soils are erodible. Crops can be grown if
intensive measures to control wind erosion are used.
4. Clays, silty clays, noncalcareous clay looms, and silty
clay looms that are more than 35 percent clay. These soils
are moderately erodible. Crops can be grown if measures to
control wind erosion are used.