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CONTROLLING EROSION ON LANDS
ADMINISTERED BY THE BUREAU OF
LAND MANAGEMENT, WINNEMUCCA
DISTRICT, NEVADA
Michael J. Zielinski
The Bureau of Land Management (BLM) Winnemucca
District consists of approximately 4 million hectares. The
Winnemucca District is located in the northern Great Basin. The extremes of climate, relief, aspect, and geologic
type all combine to produce a diverse environment. Numerous wildfires occur within the district. The dominant
vegetative communities where fire occurrence is most frequent are the Wyoming big sagebrush (Artemisia tridentata wyomingensis) and the shadscale CA.triplex confertifolia) communities.
The following information is extracted from the "Ten
Year Fire History Report" for the district or the "Bum
Area Reports" for each fire.
In the past 10 years, 602 fires have burned 305,000
hectares. Fire size varies, but fires between 17,000 and
46,000 hectares are not uncommon. The peak fire year
was 1985, burning 208,800 hectares.
Seeding projects have been conducted on 25,500 hectares. The objectives of the fire rehabilitation program
are:
barriers to livestock to assure that grazing does not take
place. Rest from grazing provides the native species sufficient time for seed germination and for development of
adequate seedling root growth to prevent uprooting by
grazing. It also allows perennials and seedlings to develop good vigor and produce viable seed.
SEEDING
Seedings are implemented in areas that lack sufficient
perennial species for natural revegetation. Rangeland
drills or broadcast seeders are used. Rangeland drills can
be used on slopes up to 25 percent. Aerial seeding is not
used in the district because of vesicular crusting and low
annual precipitation. No broadcasted seed is planted into
Wyoming big sagebrush or shadscale communities, unless
seed is covered by chaining or harrowing.
Of the hectares seeded (25,500), 78 percent (19,900
hectares) occurs in the Wyoming big sagebrush communities, 14 percent (3,600 hectares) in the basin big
sagebrush (Artemisia tridentata tridentata) communities,
5 percent (1,300 hectares) in the mountain big sagebrush
(Artemisia vaseyana) communities, and 3 percent (800
hectares) in the shadscale communities.
Seed prescription is based on pure live seeds per square
foot (PLS/ft2 ). Seeding rates have a minimum of 20 PLS/
ft 2 for drills; rates range between 20 to 40 PLS/ft2• The
rate for broadcasted seed is double the drill rate.
1. Prevent loss of soil through erosion and loss of onsite productivity of ecological sites. ("Ecological site" and
"range site" are synonymous; an ecological site or range
site is a distinctive kind of rangeland that differs from
other kinds of rangeland in its ability to produce a characteristic natural plant community; definition from section 302.1 National Range Handbook.)
2. Prevent damage to property on and off site (such as
loss of structures, roads, irrigation systems, power and
communication lines).
3. Prevent the invasion of burned areas by highly flammable annual plants that produce a high potential for a
rebum and additional site deterioration.
VEGETATIVE WATERWAYS
Vegetative waterways are drainage channels that have
been seeded by broadcasting seed. Seed prescriptions are
a combination of grasses and forbs. This method is used
in steep terrain, where access by rangeland drills is not
possible.
NATURAL REVEGETATION
Natural revegetation is the principle rehabilitation
method for 92 percent of the burned areas (this information is extracted from the district fire reports). Areas are
closed to livestock grazing for a minimum of two growing
seasons. Livestock closure applies to all treatment
methods.
Livestock closure support facilities are necessary to
control livestock grazing. These facilities create physical
EROSION MATS
Erosion mats have been used to armor headcuts or
line drainage channels. Erosion mats are tough, waterpermeable fabrics. Before placing the erosion mat, the
area is broadcast seeded. The erosion mat is rolled onto
the ground surface and is anchored.
GREENSTRIPPING
Poster paper presented at the Symposium on Ecology, Management,
and Restoration oflntermountain Annual Rangelands, Boise, ID,
May 18-22, 1992.
Michael J. Zielinski is a Soil Scientist, U.S. Department of the Interior,
Bureau of Land Management, Winnemucca District, Winnemucca, NV.
The greenstripping treatment is intended to slow or
stop the spread of wildfire by placing strips of fireresistant vegetation strategically on the landscape to
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reduce wildfire size and frequency (PeDant 1990). This
treatment is used principally in the Wyoming big sagebrush communities. A seedbed is prepared by removing
existing vegetation.
A common method of removing vegetation and preparing a seedbed is spring plowing, which is done to set seed
of annual species, to reduce competition. The strips lay
fallow during the summer and early fall. Drill seedings
are completed in the fall, from mid-October through
November. The strips are generally 100 meters wide
and adjacent to existing roads. The roads serve as access
points for fll'e suppression crews.
are highly susceptible to annual plant invasion by cheatgrass (Bromus tectorum).
The common soil subgroups for Wyoming big sagebrush
communities are: Durixerollic or Xerollic Camborthids,
Durixerollic or Xerollic Haplargids, Durixerollic or Xerollic
Natrargids, Xerollic Durorthids, and Xerollic Nadurargids.
Annual precipitation is between 8 and 12 inches. The potential vegetative composition is about 55 percent grasses,
40 percent shrubs, and 5 percent forbs.
Basin Big Sagebrush-Basin big sagebrush communities have poor natural recovery for shrubs, from a trace
to one plant per meter. The common soil subgroup for the
basin big sagebrush communities is Xeric Torripsamments. Annual precipitation is between 8 and 10 inches.
The potential vegetative composition is about 55 percent
grasses, 35 percent shrubs, and 10 percent forbs.
TREND DETERMINATION
Treatments discussed here are based on monitoring
(Community Structure Analysis and Density Studies) and
observation of fires beginning in 1984. Studies are read
for 3 consecutive years, then at 5-year intervals to determine trend.
Mountain Big Sagebrush-Mountain big sagebrush
communities' natural recovery occurs within 15 years and
has been one to two shrubs per meter. ·In mid status,
shrubs will recover, but native grasses and forbs will be
lacking.
The common soil subgroups for the mountain big sagebrush community are Typic Haploxerolls and Typic Argixerolls. Annual precipitation is between 12 and 16 inches.
The potential vegetative composition is 65 percent grasses,
25 percent shrubs, and 10 percent forbs.
NATURAL REVEGETATION
Natural revegetation areas lack sufficient perennial
species for natural recovery or are inaccessible to mechanical equipment. To determine areas that have natural
recovery potential, the soil and ecological site must be determined. Third-order soil surveys are the basis for determining ecological sites.
From the ecological site, the ecological status or seral
stage can be determined. Ecological status or seral stage
is determined by comparing the present plant community
with that of the climax community. A rating of 0-25 is
early, 26-50 mid, 51-75late, and 75-100 climax. Successful natural recovery will occur in late or climax status.
Seeding failures will result in areas of late status, due
to competition from existing perennial species.
Four vegetative communities will be discussed: the
shadscale, the Wyoming big sagebrush, the basin big
sagebrush, and the mountain big sagebrush.
SEEDINGS
Seeding treatments are based on soil suitability as
rated by the Nevada State Seeding Guide, and ecological
status. Soil suitability is determined by reviewing the
third-order soil survey and by an on-site investigation.
Ifleft to natural rehabilitation, areas would be invaded by
less-desirable annual plant species.. Sites with similar
characteristics, after past burns, have become dominated
by annual plant species such as cheatgrass, halogeton
(Halogeton glomeratus), mustards (Brassica), and Russian
thistle (Salosola kali).
Areas that are dominated by annual species have a
high potential for recurring wildfires, which eventually
degrade a site beyond its ability to naturally regain the
potential ecological community it was once capable of producing. Young and Evans (1978) stated, "The reestablishment of downy brome (cheatgrass) dominance predisposes
the vegetation to recurring wildfires and cyclic environmental degradation. Downy brome has the inherent competitive ability to close seral communities to seedlings of
perennial grasses. Downy brome is the symbol of environmental degradation if the pristine vegetation is used as
the benchmark of judging range condition."
Seedings provide sufficient competition to prevent total
annual species invasion. This in tum maintains site productivity by preventing frequent wildfires.
Shadscale-Shadscale communities in late ecological
status naturally recover within 5 years. Natural recovery
results in two to five shrubs per meter. The reestablished
shrubs are from seed reserves in the soil.
It is essential that areas are rested from livestock grazing for a minimum of 2 years. First-year shadscale seedlings lack spines and are highly susceptible to grazing.
Plants develop spines in the second year. Without livestock controls, these plant communities will be dominated
by annual species. Early and mid status communities
will be dominated by annual species.
The common soil subgroups for these plant communities are: Durie or Typic Camborthids, Durie or Typic
Natrargids, Typic Durorthids, and Typic Nadurargids.
Precipitation is between 4 and 8 inches. The potential
vegetative composition is about 70 percent shrubs, 25 percent grasses, and 5 percent forbs.
SEEDING SUCCESS BY PLANT
COMMUNITIES
Wyoming Big Sagebrush-Wyoming big sagebrush
communities have the poorest natural recovery for shrubs.
Eight years of monitoring indicate that no Wyoming big
sagebrush recovery has occurred. These plant communities
Seedings in shadscale have resulted in failure. Seeding
success is between 50 and 75 percent in the Wyoming big
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sagebrush areas. Seeding success is less then 25 percent
in the basin big sagebrush (sandy) areas. Aerial seeding
in the mountain big sagebrush areas has resulted in failure. Drilled seedings have not been conducted in these
areas; steep slopes have been the limiting factor.
formation. Livestock have had a detrimental effect by severely grazing established vegetation, which has reduced
the effectiveness of this treatment.
The common soil subgroup for this treatment is
Fluventic Haploxerolls. Annual precipitation is between
12 and 16 inches.
SEED PRESCRIPTIONS
EROSION MATS
Seed prescriptions are based on surface texture, moisture regime, available water capacity, salinity, sodicity,
and surface morphological type. Each seed prescription is
adapted to the particular soil type and ecological site. A
slight soil difference can make the difference between a
success or failure.
For example, consider an 810-hectare burn composed of
485 hectares of a Durie Natrargid in late status and 325
hectares of a Durixerollic Natrargid in mid status. Soil
characteristics are identical except for percent organic
carbon-0.4 to 0.6 and 0.6 to 0.8, respectively. What is
the best rehabilitation option? Seed the entire area, allow
for natural recovery, or provide a combination of both?
The Durie Natragids will recover naturally. A seeding
of crested wheatgrass will have less than a 50 percent
chance of survival. The Durixerollic Natragids will be
dominated by annual species, unless the area is seeded.
H the objective of seeding is erosion control, then adapted
species must be planted. A seeding failure will not remedy the situation. Seed prescriptions thus include native
and introduced species.
This treatment is rarely used, because the cost of installation is generally prohibitive. This treatment is used
to lessen sediment in watershed areas that have viable
fisheries.
GREENSTRIPPING
Greenstripping is a new technique used for slowing or
stopping the spread of wildfires. This technique was first
tried in the mid-1980's in Idaho. Success of the program
has resulted in implementation of similar projects in the
Winnemucca District.
Reducing wildfire frequency and size results in important benefits. By protecting fire-susceptible vegetation
types from wildfire, important rangeland resources such
as wildlife habitat, livestock forage, and watershed stability are maintained. Loss of private structures and properties on urban/rural interfaces with public rangelands is
reduced. Large annual rangelands are broken into
smaller, more fire-manageable blocks. Suppression and
rehabilitation costs are reduced (Pellant 1990).
Sagebrush vegetation types in the Great Basin evolved
in an environment that included wildfire at return intervals of32 to 70 years (Wright and others 1979). Alien annual species were introduced and rapidly expanded in extent and dominance on degraded rangelands (Young and
others 1972). Cheatgrass is one of the alien annual plants
that is highly flammable, has a high potential for reburn,
and causes additional site deterioration. The recurring
wildfires eventually degrade the sites beyond their ability
to naturally regain the ecological community they once
could produce (Young and Evans 1978). Greenstripping
is a treatment used to reverse this trend.
COVER CROPS
Seedings of cover crops for erosion control of blowing
sands have two purposes: (1) erosion control and (2) protection of existing perennial species for reestablishment.
Controlling wind erosion is a major problem within the
Winnemucca District. Fine sand surface textures left barren after fires have created severe erosion problems.
Rapid erosion control treatments are essential to prevent
damage to resources. Wind erosion can remove 6 to 19
millimeters, or 62 to 185 tons of soil per hectare per year.
Cover crops of cereal rye are a quick solution to this problem, as they stabilize the surface for reestablishment of
perennial or annual vegetation.
Cover crops have been used to prevent dust hazard
along roads or adjacent to urban development. Strong
winds periodically create severe dust hazards, which have
limited visibility on State highways and Interstate 80.
Traffic has been forced to stop or to travel only one way.
The potential exists for vehicular accidents and serious
personal injuries. The worst accident was a chain collision of 23 vehicles on Interstate 80.
CONCLUSIONS
Third-order soil surveys provide information resource
managers need to develop cost-effective and successful
vegetative erosion control treatments. Management options and success can be related directly to the predictability of the soil type's response to treatment, which is
determined through analysis of the area's soil and ecological status. The objectives of the fire rehabilitation program can be accomplished.
VEGETATIVE WATERWAYS
REFERENCES
Vegetative waterways are an effective erosion control
treatment in mountainous areas. Vegetative waterways
are natural drainage channels, seeded to grasses and
forbs. Seeding success has been 100 percent on eight
projects. The vegetation serves as a filter to trap sediment and decreases velocity of runoff, preventing gully
Pellant, Mike. 1990. The cheatgrass-wildfire cycle-are
there any solutions? In: McArthur, E. D.; Romney,
E. M.; Smith, S.D.; Tueller, P. T., comps. Proceedingssymposium on cheatgrass invasion, shrub die-off, and
other aspects of shrub biology and management; 1989
145
April 5-7; Las Vegas, NV. Gen. Tech. Rep. INT-276.
Ogden, UT: U.S. Department of Agriculture, Forest Service, Intermountain Research Station: 11-18.
Wright, H. A.; Neuenschwander, L. F.; Britton, C. M.
1979. The role and use of fire in sagebrush and pinyonjuniper plant communities: a state-of-the-art review.
Gen. Tech. Rep. INT-58. Ogden, UT: U.S. Department
of Agriculture, Forest Service, Intermountain Forest
and Range Experiment Station. 48 p.
Young, J. A.; Evans, R. A. 1978. Population dynamics
after wildfire in the sagebrush grasslands. Journal of
Range Management. 31: 283-289.
Young, J. A.; Evans, R. A.; Major, J. 1972. Alien plants in
the Great Basin. Journal of Range Management. 25:
194-201.
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