FLOOD09931

• County: Statewide
• Community: Urbanizing Areas of Colorado
• Basin: Statewide
• Title: A Guide for Erosion & Sediment Control in Urbanizing Areas of Colorado
• Date: 1/1/1973
• Prepared For: State of Colorado
• Prepared By: USDA Soil Conservation Service
• Floodplain - Doc Type: Educational/Technical/Reference Information

Problem 2

Using the same factors except for "V" (vegetative
cover), calculate the estimated soil loss from wind ifthe
area has a cover of annual rye. The rye has an air dry
weight of 600 Ibs.

Step I Refer to figure 12 to determine the pounds of
flat small grain per acre that equals 600 lbs of
rye.

Step 2 600 lb. of annual rye is the equivalent of 1250
lbs of flat small grain residue. Refer to the
applicable section of Table 3 and predict the
soil loss from wind erosion. The estimated
soil loss is approximately 1.5 tons/Ac/Yr.

Problem 3

Using the same values except for "V," estimate the soil
loss if the disturbed area was mulched with 1200 #IAc
of wheat straw and crimped into the soil for stability.

Step I Refer to figure 12 to determine the amount of
flat small grain residue that is equivalent to
1200 lbs per acre of straw mulch adequately
crimped into the soil.

Step 2 Mulching with 1200 Ibs of straw is equivalent
to approximately 800 lbs of flat small grain
residue. Refer to the applicable section of
Table 3 to determine the soil loss from wind
erosion. The estimated soil loss is approxi-
mately 5.5 tons per acre.

References

1. Rocky Mountain Horticulture, George Kelly, 1967

2. "How to Arrange and Space Trees and Shrubs in
Field Windbreaks," Ralph A. Read, USDA Rocky
Mountain Forest and Range Experiment Station,
USDA-Forest Service.

3. "The Farmstead Windbreak," Dale L. Shaw, Col-
orado State Forest Service, Colorado State Univer-
sity, November, 1974.

TABLE 2

Wind Erodibility Groups

Clodiness- Wind
Dry Soil Erodibility
Aggregates Index
Over 0.84 (I)
~ mm Percent T/Ac/Yr
I Very fine, fine, and
medium sands; dune sands 3 220
2 Loamy sands; loamy fine
sands 10 134
3 Very fine sandy loams,
fine sandy loams; sandy
loams 25 86
4 Clays; silty clays; non-
calcareous clay loams and
silty clay loams with more
than 35% clay content 25 86
4L Calcareous loams and silt
loams; calcareous clay
loams and silty clay loams
with less than 35% clay
content
5 Non-calcareous loams
and silt loams with less
than 20% clay content;
sandy clay loams; sandy
clays 40 56
6 Non-calcareous loams
and silt loams with more
than 20% clay content;
noncalcareous clay loams
with less than 35% clay
content 45 48
7 Silts; non-calcareous silty
clay loams with less than
35% clay content 50 38
8 Very wet or stony; not
subject to wind erosion

4. Soil Erosion: Prediction and Control, Proceedings
of a National Conference on Soil Erosion, Soil Con-
servation Society of America, May /976.

5. Wind Erosion Control on Cropland, D. G. Craing,
J. W. TureUe, USDA-SCS, /964.

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