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Ecological site R069XY058CO

Limestone Breaks

Last updated: 4/30/2024
Accessed: 11/21/2024

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General information

Provisional. A provisional ecological site description has undergone quality control and quality assurance review. It contains a working state and transition model and enough information to identify the ecological site.

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Figure 1. Mapped extent

Areas shown in blue indicate the maximum mapped extent of this ecological site. Other ecological sites likely occur within the highlighted areas. It is also possible for this ecological site to occur outside of highlighted areas if detailed soil survey has not been completed or recently updated.

MLRA notes

Major Land Resource Area (MLRA): 069X–Upper Arkansas Valley Rolling Plains

MLRA 69 is in the Arkansas Watershed of southeastern (SE) Colorado. It consists of rolling plains, river valleys, and canyonlands. The Arkansas River flows from the Rocky Mountains to Kansas. Tributaries include the Huerfano and Purgatoire Rivers. The MLRA is traversed by Interstate 25 and U.S. Highway 50, and includes the cities of Pueblo, La Junta, and Lamar. Other cities include Cañon City, and Walsenburg. Bent's Fort was once a major trading post along the Santa Fe Trail. The majority of land use is rangeland (greater than 75 percent), and 6 percent cropland. The remainder is urban, recreation, etc. Land ownership is mostly private. Federal lands include U.S. Forest Service Comanche National Grassland, Department of Defense Piñon Canyon Maneuver Site and Fort Carson. There is a minor amount of Bureau of Land Management and other federal land. State areas include Pueblo and John Martin reservoirs. Elevations MLRA-wide are 3,700 to 6,400 feet.

The "Dust Bowl" region (1930s) included SE Colorado, which is periodically affected by severe drought. Dust storms may form during drought years, in windy periods. Annual precipitation is 10 to 16 inches. Precipitation occurs mostly during the growing season, often during rapidly developing thunderstorms. Mean annual air temperature (MAAT) is 48 to 52 degrees Fahrenheit. Summer temperatures may exceed 100 degrees Fahrenheit. Evapotranspiration rates are high. Winter temperatures may be subzero. Snowfall varies from 20 to 40 inches per year. Blizzards can form quickly.

Classification relationships

MLRA 69 is in the Piedmont and Raton Sections of the Great Plains Province. The MLRA is further defined by Land Resource Units (LRUs) A, B, and C. The modal concepts of each LRU can be defined by soil properties and annual precipitation zones (PZ). Other features, such as climate, geology, landforms, and key vegetation, further refine these concepts and are described in the Ecological Site Description (ESD).

LRU A (10 to 12 inches PZ) is 2.4 million acres in the central portion of MLRA 69. There is irrigated cropland in the Arkansas Valley. Precipitation is too limited for dryland crops. Most of LRU A is rangeland, and includes the Comanche National Grassland (USFS). This LRU is in portions of Bent, Crowley, Otero, and Pueblo counties. Soil Moisture Regime is Ustic Aridic. The Mean Annual Air Temperature (MAAT) is 51 to 54 degrees Fahrenheit.

LRU B (12 to 14 inches PZ) is 4.7 million acres and includes portions of Baca, Bent, Crowley, El Paso, Fremont, Kiowa, Las Animas, Lincoln, Prowers, and Pueblo counties. Most of the LRU is in rangeland. Land uses include irrigated and dry cropland, small acreage and urban ownership. Land east of Interstate 25 remains largely agricultural. Canyonlands are in the southern half and include Piñon Canyon Maneuver Site and the Picket Wire Canyon of the Comanche National Grasslands. Soil moisture regime is Ustic Aridic. The mean annual air temperature is 50 to 54 degrees Fahrenheit.

The Limestone Breaks Ecological Site, LRUs A and B, was developed from an earlier version of the Limestone Breaks Ecological Site (2005, revised in 2007). This earlier version of the Limestone Breaks Ecological Site (2005) was based on input from Natural Resources Conservation Service (formerly Soil Conservation Service) and historical information obtained from the Limestone Breaks Range Site descriptions (1975, revised 1983). This ESD meets the Provisional requirements of the National Ecological Site Handbook (NESH). This ESD will continue refinement towards an Approved status according to the NESH.

Ecological site concept

This ecological site occurs in an upland position on slopes of greater than 10 percent. The soil depth is less than 20 inches to limestone bedrock.

Associated sites

R069XY042CO	Clayey Plains This ecological site is commonly adjacent.
R069XY048CO	Shale Breaks This ecological site is commonly adjacent.
R069XY006CO	Loamy Plains This ecological site is commonly adjacent.
R069XY047CO	Alkaline Plains This ecological site is commonly adjacent.
R069XY064CO	Gravel Breaks This ecological site is commonly adjacent.
R069XY046CO	Shaly Plains This ecological site is commonly adjacent.

Similar sites

R069XY048CO	Shale Breaks This ecological site is over shale bedrock.
R069XY053CO	Sandstone Breaks This ecological site is over sandstone bedrock.
R069XY064CO	Gravel Breaks This ecological site has a soil depth of greater than 20 inches, and is influenced by rock fragments.

R069XY048CO

Shale Breaks

This ecological site is over shale bedrock.

R069XY053CO

Sandstone Breaks

This ecological site is over sandstone bedrock.

R069XY064CO

Gravel Breaks

This ecological site has a soil depth of greater than 20 inches, and is influenced by rock fragments.

Table 1. Dominant plant species

Tree	(1) Juniperus monosperma (2) Pinus edulis
Shrub	(1) Artemisia bigelovii (2) Krascheninnikovia lanata
Herbaceous	(1) Bouteloua curtipendula (2) Hesperostipa neomexicana

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Physiographic features

This site occurs on plains.

Table 2. Representative physiographic features

Landforms	(1) Hill (2) Ridge (3) Scarp (4) Hogback (5) Mesa (6) Cuesta
Runoff class	Low to very high
Flooding frequency	None
Ponding frequency	None
Elevation	1,128 – 1,951 m
Slope	1 – 65%
Ponding depth	0 cm
Water table depth	152 cm
Aspect	Aspect is not a significant factor

Climatic features

Approximately 75 percent of the annual precipitation occurs during the growing season from mid-April to late September. Snowfall can vary greatly from year to year and can range from 20 to 40 inches per year. Winds are estimated to average 6 to 7 miles per hour annually. Daytime winds are generally stronger than nighttime winds. Occasional strong storms may bring brief periods of high winds with gusts to more than 60 miles per hour. The average length of the freeze-free period (28 °F) is 168 days. The average last freeze in the spring is April 22nd, and the average date of first freeze in fall is October 7th. The average length of the frost-free period (32 °F) is 149 days. The last frost in the spring is May 5th, and the average date for first frost in the fall (32 °F), is October 1. July is the hottest month, and January is the coldest. It is not uncommon for temperature to exceed 100 degrees Fahrenheit during the summer. Summer humidity is low and evaporation is high. The winters are characterized with frequent northerly winds, producing severe cold and temperatures dropping to -30 degrees Fahrenheit.

LRU A, in the Arkansas River Valley, is the hottest and driest portion of the MLRA. Mean Annual Precipitation (MAP) is 10 to 12 inches, and Mean Annual Air Temperature (MAAT) is 51 to 54 degrees Fahrenheit. LRU B is the largest extent. MAP is 12 to 14 inches, and MAAT is 50 to 54 degrees Fahrenheit.

Table 3. Representative climatic features

Frost-free period (characteristic range)	127-134 days
Freeze-free period (characteristic range)	149-161 days
Precipitation total (characteristic range)	305-356 mm
Frost-free period (actual range)	121-135 days
Freeze-free period (actual range)	141-164 days
Precipitation total (actual range)	279-406 mm
Frost-free period (average)	129 days
Freeze-free period (average)	153 days
Precipitation total (average)	330 mm

Characteristic range

Actual range

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Figure 2. Monthly precipitation range

Characteristic range

Actual range

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Figure 3. Monthly minimum temperature range

Characteristic range

Actual range

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Figure 4. Monthly maximum temperature range

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Figure 5. Monthly average minimum and maximum temperature

Figure 6. Annual precipitation pattern

Figure 7. Annual average temperature pattern

Climate stations used

(1) EADS [USC00052446], Eads, CO
(2) ORDWAY 21 N [USC00056136], Ordway, CO
(3) PUEBLO RSVR [USC00056765], Pueblo, CO
(4) PUEBLO MEM AP [USW00093058], Pueblo, CO
(5) LA JUNTA 20 S [USC00054726], La Junta, CO
(6) CHERAW 1 N [USC00051539], La Junta, CO
(7) ROCKY FORD 2 SE [USC00057167], Rocky Ford, CO
(8) ORDWAY 2 ENE [USC00056131], Ordway, CO
(9) TACONY 13 SE [USC00058157], Boone, CO

Soil features

The soils of this site are very shallow or shallow. They are well drained with moderate slow through moderately rapid permeability. The surface layer thickness ranges from 2 to 6 inches. The soil moisture regime is ustic aridic. The soil temperature regime is mesic. Parent material kind is slope alluvium over residuum weathered from limestone. Parent material originated from limestone.

Major soil series correlated to this ecological site include Penrose.

Revisions to soil surveys are on-going. For the most recent updates, visit the Web Soil Survey, the official site for latest soils information: http://websoilsurvey.nrcs.usda.gov/app/WebSoilSurvey.aspx.

Table 4. Representative soil features

Parent material	(1) Alluvium – limestone
Surface texture	(1) Channery loam
Family particle size	(1) Loamy
Drainage class	Well drained
Permeability class	Moderately slow to moderately rapid
Soil depth	23 – 51 cm
Surface fragment cover <=3"	0 – 35%
Surface fragment cover >3"	0 – 5%
Available water capacity (0-101.6cm)	9.14 – 20.32 cm
Calcium carbonate equivalent (0-101.6cm)	5 – 75%
Electrical conductivity (0-101.6cm)	0 – 4 mmhos/cm
Sodium adsorption ratio (0-101.6cm)	0 – 10
Soil reaction (1:1 water) (0-101.6cm)	7.4 – 9
Subsurface fragment volume <=3" (Depth not specified)	0 – 35%
Subsurface fragment volume >3" (Depth not specified)	0 – 5%

Ecological dynamics

The information in this ESD, including the state-and-transition model (STM), was developed using archeological and historical data, professional experience, and scientific studies. The information is representative of a complex set of plant communities. The plant composition has been determined by study of rangeland relic areas, areas protected from excessive disturbance, seasonal-use pastures, short-duration or time-controlled grazing strategies, and historical accounts.

Not all scenarios or plants are included. Key indicator plants, animals, and ecological processes are described to inform land management decisions.

This region was historically occupied by large grazing animals, such as bison, along with pronghorn and mule deer. Deer and pronghorn are widely distributed throughout the MLRA. This is an important site for livestock grazing, especially cattle.

Drought has historically impacted the vegetation of this region. Changes in species composition vary depending upon the duration and severity of the drought cycle and prior grazing management. Recent drought events have increased mortality of blue grama significantly in some locales, along with other bunchgrasses, such as sand bluestem, little bluestem, needle and thread, Fendler threeawn, and squirreltail. Historic fire frequency (pre-industrial) is estimated at 15 to 20 years (Guyette, 2012), randomly distributed, and started by lightning at various times throughout the growing season. Early human inhabitants were also likely to start fires (deliberate or accidental).

The site is dominated by mid warm-season bunchgrasses (sideoats grama and little bluestem), mid cool-season bunchgrass (New Mexico Feathergrass), and short warm-season bunchgrass (blue grama). Secondary grasses are mid warm-season rhizomatous grass (galleta), and mid cool-season rhizomatous grass (western wheatgrass). Minor grasses include short warm-season bunchgrass (hairy grama, hairy tridens), mid cool-season bunchgrasses (needle and thread, Indian ricegrass and green needlegrass), and tall warm-season bunchgrass (big bluestem). Various shrubs (Bigelow sagebrush, fourwing saltbush, winterfat) and forbs (American vetch, dotted gayfeather, and purple prairieclover), occur on the site and are subdominant in composition. Other minor grasses and grass-likes are littleseed ricegrass, ring muhly, and sun sedge). Trees such as oneseed juniper and pinyon pine are present in minor amounts.

Continuous grazing without allowing for adequate recovery opportunities between grazing events causes this site to deteriorate. Grasses such as little bluestem, sideoats grama, big bluestem, switchgrass, yellow Indiangrass, New Mexico feathergrass, western wheatgrass, and needle and thread decrease in both frequency and production. Blue grama, hairy grama, and galleta increase. Forbs and shrubs such as purple prairie clover, American vetch, winterfat, and fourwing saltbush decrease. Mid- and tallgrasses can eventually be removed from the plant community. Over the long-term, heavy, continuous use results in large amounts of bare ground. Species such as Fendler's threeawn, sand dropseed, mat loco, sessile nailwort, small soapweed, broom snakeweed, and annuals increase or invade the site.

Drier and warmer climatic conditions exist in the central portion of MLRA 69. This area includes the eastern half of Pueblo county, northern Otero, extreme northwestern Bent, western edge of Kiowa, southern edge of Lincoln and all of Crowley County. These conditions are primarily caused by a rain shadow effect from the southern Rocky Mountains. Evapotranspiration rates (atmospheric demand) are higher in this area of MLRA 69. Total annual production is typically lower.

Southeastern Colorado was strongly affected by extended drought conditions in the “Dust Bowl” period of the 1930s, with recurrent drought cycles in the 1950s and 1970s. Extreme to exceptional drought conditions have re-visited the area from 2002 to 2012, with brief interludes of near normal to normal precipitation years. “During periods of drought, high winds give rise to the dust storms which are especially characteristic of the southeastern plains (WRCC, 2022).” Recent drought events have increased mortality of blue grama upwards of 80 percent in some locales. The long-term effects of these latest drought years have yet to be determined.

Growth of native cool-season plants begins about April 15 and continues to mid-June. Native warm-season plants begin growth about May 1 and continue to about August 15. Regrowth of cool-season plants occurs in September and October in most years, depending on moisture. For detailed information, visit the Western Regional Climate Center website at https://wrcc.dri.edu/.

State and transition model

More interactive model formats are also available. View Interactive Models
Click on state and transition labels to scroll to the respective text

Ecosystem states

1. Reference State

2. Blue Grama Dominant State

3. Eroded State

T1A	-	Heavy, continuous grazing. Lack of fire.
R2A	-	Prescribed grazing. Prescribed fire.
T2A	-	Heavy, continuous grazing. Lack of fire.

State 1 submodel, plant communities

1.1. Bouteloua curtipendula-Hesperostipa neomexicana (sideoats grama-New Mexico feathergrass).

1.2. Bouteloua gracilis-Pleuraphis jamesii (blue grama-galleta).

1.3. Bouteloua curtipendula-Hesperostipa neomexicana (sideoats grama-New Mexico feathergrass) Low Plant Density Community.

1.1A	-	Heavy, season-long grazing. Lack of fire.
1.1B	-	Non-use. Lack of fire.
1.2A	-	Prescribed grazing. Prescribed fire.
1.3A	-	Prescribed grazing. Prescribed fire.

State 2 submodel, plant communities

2.1. Bouteloua gracilis (blue grama) Community.

State 3 submodel, plant communities

3.1. Bromus tectorum-Salsola (cheatgrass-russian thistle) Eroded Community.

State 1
Reference State

The Reference State is characterized by three plant community phases that represent the natural range of variability and disturbance regimes within the site. These plant community phases are maintained by a historic fire frequency (estimated to be on 15 to 20 year intervals), grazing by large ungulates, and adequate recovery periods.

Dominant plant species

oneseed juniper (Juniperus monosperma), tree
twoneedle pinyon (Pinus edulis), tree
Bigelow sage (Artemisia bigelovii), shrub
James' seaheath (Frankenia jamesii), shrub
winterfat (Krascheninnikovia lanata), shrub
fourwing saltbush (Atriplex canescens), shrub
sideoats grama (Bouteloua curtipendula), grass
New Mexico feathergrass (Hesperostipa neomexicana), grass
little bluestem (Schizachyrium scoparium), grass

Community 1.1
Bouteloua curtipendula-Hesperostipa neomexicana (sideoats grama-New Mexico feathergrass).

This plant community is the interpretive plant community for this site and is considered to be the reference plant community. This community evolved with grazing by large herbivores and is suited to grazing by domestic livestock. Historically, fires likely occurred infrequently. This plant community can be found on areas that are grazed and where the grazed plants receive adequate periods of recovery during the growing season. The potential vegetation is about 70 to 80 percent grasses and grass-likes, 10 to 15 percent forbs and 10 to 15 percent woody plants. The principal grasses that dominate this community are sideoats grama, little bluestem, New Mexico Feathergrass, and blue grama. Secondary grasses are galleta, western wheatgrass, Indian ricegrass, hairy grama, and needle and thread. Dominant forbs include purple prairie clover, American vetch, dotted gayfeather, mat loco, sessile nailwort, and Hood’s phlox. Bigelow sagebrush, winterfat, fourwing saltbush, skunkbush sumac, and golden currant are key shrubs. Oneseed juniper and pinyon pine may be present in very small amounts. This is a sustainable plant community in terms of soil stability, watershed function, and biological integrity. Litter is properly distributed where vegetative cover is continuous. Some litter movement may occur on steeper slopes. Decadence and natural plant mortality is very low. Community dynamics, nutrient cycle, water cycle, and energy flow are functioning properly. This community is resistant to many disturbances with the exception of heavy, continuous grazing, tillage, and development into urban or other uses. Areas having lost all vegetation, such as livestock and vehicle trails are subject to high erosion rates and extreme runoff. Total annual production, during an average year, ranges from 350 to 900 pounds of air-dry weight and averages 600 pounds.

Dominant plant species

oneseed juniper (Juniperus monosperma), shrub
twoneedle pinyon (Pinus edulis), shrub
sideoats grama (Bouteloua curtipendula), grass
New Mexico feathergrass (Hesperostipa neomexicana), grass
little bluestem (Schizachyrium scoparium), grass

Figure 8. Annual production by plant type (representative values) or group (midpoint values)

Table 5. Annual production by plant type

Plant type	Low (kg/hectare)	Representative value (kg/hectare)	High (kg/hectare)
Grass/Grasslike	269	501	785
Forb	62	84	106
Shrub/Vine	62	84	106
Tree	–	3	11
Total	393	672	1008

Figure 9. Plant community growth curve (percent production by month). CO6901, Warm-season/cool-season co-dominant; MLRA-69; upland fine textured soils..

Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
J	F	M	A	M	J	J	A	S	O	N	D
0	0	5	10	20	30	20	10	3	2	0	0

Community 1.2
Bouteloua gracilis-Pleuraphis jamesii (blue grama-galleta).

This plant community developed with heavy, season-long grazing without adequate recovery time during the growing season and lack of fire. The dominant grass is typically blue grama with increased amounts of galleta. New Mexico feathergrass can increase with spring rest or recurring summer herbivory. Sideoats grama and little bluestem are still present as secondary grasses in the community. Big bluestem, Indiangrass, switchgrass, needle and thread, and western wheatgrass have been significantly reduced. Forbs and shrubs that have increased are mat loco, sessile nailwort, Hood’s phlox, hairy goldaster, Cuman ragweed, slimflower scurfpea, small soapweed, and broom snakeweed. Purple prairie clover, American vetch, winterfat, fourwing saltbush, currants, and skunkbush sumac have been reduced. Oneseed juniper and pinyon have increased. Plant frequency, production, and litter levels are lower compared to the reference plant community. Soil erosion may be a concern at this point, especially on high travel or impact areas. Some flow paths may be connected. Water cycle and nutrient cycle are beginning to be affected by the reduction of key grasses, forbs, and shrubs. Total annual production can vary from 200 to 500 pounds of air-dry vegetation per acre and averages 300 pounds during an average year.

Dominant plant species

oneseed juniper (Juniperus monosperma), tree
twoneedle pinyon (Pinus edulis), tree
soapweed yucca (Yucca glauca), shrub
broom snakeweed (Gutierrezia sarothrae), shrub
blue grama (Bouteloua gracilis), grass
James' galleta (Pleuraphis jamesii), grass

Figure 10. Plant community growth curve (percent production by month). CO6903, Warm-season dominant, cool-season sub-dominant; MLRA-69; upland fine textured soils..

Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
J	F	M	A	M	J	J	A	S	O	N	D
0	0	0	5	15	35	25	15	5	0	0	0

Community 1.3
Bouteloua curtipendula-Hesperostipa neomexicana (sideoats grama-New Mexico feathergrass) Low Plant Density Community.

This plant community developed under years of non-use and lack of fire. Plant species resemble the reference plant community but species frequency and production are reduced. Eventually, litter levels become high enough to cause stagnation and mortality of various species such as little bluestem, sideoats grama, big bluestem, Indiangrass, and blue grama. Bunchgrasses typically develop dead centers and rhizomatous grasses form small communities because of a lack of stimulation by grazing animals. Initially, high surface litter levels will minimize erosion. Advanced stages of non-use or lack of fire can result in lower vigor plants, causing an increase in bare areas. These areas are susceptible to water erosion, especially on steeper slopes. Total annual production can vary from 250 to 950 pounds of air-dry vegetation per acre.

Dominant plant species

oneseed juniper (Juniperus monosperma), tree
twoneedle pinyon (Pinus edulis), tree
Bigelow sage (Artemisia bigelovii), shrub
James' seaheath (Frankenia jamesii), shrub
winterfat (Krascheninnikovia lanata), shrub
fourwing saltbush (Atriplex canescens), shrub
sideoats grama (Bouteloua curtipendula), grass
New Mexico feathergrass (Hesperostipa neomexicana), grass
little bluestem (Schizachyrium scoparium), grass

Figure 11. Plant community growth curve (percent production by month). CO6902, Warm-season/cool-season co-dominant, excess litter; MLRA-69; upland fine textured soils..

Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
J	F	M	A	M	J	J	A	S	O	N	D
0	0	3	7	22	33	18	12	5	0	0	0

Pathway 1.1A
Community 1.1 to 1.2

Recurring heavy, seasonal herbivory without adequate recovery opportunity between grazing events and lack of fire shift this plant community to the 1.2 community.

Pathway 1.1B
Community 1.1 to 1.3

Non-use and no fire moves this plant community to the 1.3 community. Lack of disturbance causes the plants to become less vigorous, crowns of plants begin to die, and plant canopy begins to open up with more bare ground apparent.

Pathway 1.2A
Community 1.2 to 1.1

A grazing system with a forage and livestock balance and prescribed fire will return this community to the reference community.

Conservation practices

Prescribed Burning
Prescribed Grazing

Pathway 1.3A
Community 1.3 to 1.1

A grazing system with a forage and livestock balance and prescribed fire will return this community to the reference community.

Conservation practices

Prescribed Burning
Prescribed Grazing

State 2
Blue Grama Dominant State

The Blue Grama Dominant State is represented by one plant community phase. The tallgrasses and more palatable forbs and shrubs have been replaced by less palatable species. A major shift in species composition and plant functional groups has taken place. Nutrient and water cycles have been negatively affected due to the loss of nitrogen fixing forbs and deeper-rooted plants. Bare ground and soil erosion have increased. Rills and pedestaled plants with exposed roots are apparent. The loss of dominant and subdominant structural/functional groups reduces the biodiversity and productivity.

Dominant plant species

oneseed juniper (Juniperus monosperma), tree
twoneedle pinyon (Pinus edulis), tree
broom snakeweed (Gutierrezia sarothrae), shrub
soapweed yucca (Yucca glauca), shrub
blue grama (Bouteloua gracilis), grass
hairy grama (Bouteloua hirsuta), grass
James' galleta (Pleuraphis jamesii), grass

Community 2.1
Bouteloua gracilis (blue grama) Community.

The dominant grass is blue grama. Hairy grama, Fendler's threeawn, and galleta have increased. Tallgrasses and palatable forbs and shrubs have been removed. Little bluestem and sideoats grama may exist in remnant amounts on steeper slopes. Forbs and shrubs that continue to increase are mat loco, sessile nailwort, Hood’s phlox, broom snakeweed, and small soapweed. Oneseed juniper and pinyon have increased significantly. A major shift in species composition and plant functional groups has taken place. Nutrient and water cycles have been negatively affected due to the loss of nitrogen fixing forbs and deeper-rooted plants. Bare ground has increased and soil erosion is a concern. Rills and pedestaled plants with exposed roots are apparent. Production ranges from 75 to 300 pounds of air-dry vegetation per acre per year and averages approximately 150 pounds.

Dominant plant species

oneseed juniper (Juniperus monosperma), tree
twoneedle pinyon (Pinus edulis), tree
broom snakeweed (Gutierrezia sarothrae), shrub
soapweed yucca (Yucca glauca), shrub
blue grama (Bouteloua gracilis), grass

Figure 12. Plant community growth curve (percent production by month). CO6904, Warm-season dominant; MLRA-69; upland fine textured soils..

Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
J	F	M	A	M	J	J	A	S	O	N	D
0	0	0	0	15	45	25	15	0	0	0	0

State 3
Eroded State

This state has one community. Annuals have replaced most of the perennial grasses. Litter levels have been reduced substantially. Soil erosion and bare ground have increased and may be severe on steeper slopes. Biological integrity, watershed function, and soil stability are all impaired. This state is characterized by an impairment of all ecological functions.

Dominant plant species

oneseed juniper (Juniperus monosperma), tree
twoneedle pinyon (Pinus edulis), tree
broom snakeweed (Gutierrezia sarothrae), shrub
soapweed yucca (Yucca glauca), shrub
plains pricklypear (Opuntia polyacantha), shrub
cheatgrass (Bromus tectorum), grass
James' galleta (Pleuraphis jamesii), grass
Russian thistle (Salsola), other herbaceous
burningbush (Bassia scoparia), other herbaceous

Community 3.1
Bromus tectorum-Salsola (cheatgrass-russian thistle) Eroded Community.

Bare ground has significantly increased. Remnant amounts of blue grama, hairy grama, and galleta may exist in localized areas. Small soapweed, broom snakeweed, and pricklypear cactus may remain. Annuals invading or increasing are cheatgrass, burningbush, and Russian thistle. Litter levels have been reduced substantially. Soil erosion has increased due to the increase of bare ground and may be severe on steeper slopes. Biological integrity, watershed function, and soil stability are all impaired. Total annual production can vary from 50 to 150 pounds of air-dry vegetation per acre.

Dominant plant species

oneseed juniper (Juniperus monosperma), tree
twoneedle pinyon (Pinus edulis), tree
broom snakeweed (Gutierrezia sarothrae), shrub
soapweed yucca (Yucca glauca), shrub
plains pricklypear (Opuntia polyacantha), shrub
cheatgrass (Bromus tectorum), grass
James' galleta (Pleuraphis jamesii), grass
Russian thistle (Salsola), other herbaceous
burningbush (Bassia scoparia), other herbaceous

Figure 13. Plant community growth curve (percent production by month). CO6903, Warm-season dominant, cool-season sub-dominant; MLRA-69; upland fine textured soils..

Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
J	F	M	A	M	J	J	A	S	O	N	D
0	0	0	5	15	35	25	15	5	0	0	0

Transition T1A
State 1 to 2

Heavy, continuous grazing without adequate recovery periods between grazing events and lack of fire shift this state to the Blue Grama Dominant State.

Restoration pathway R2A
State 2 to 1

Prescribed grazing that allows for adequate recovery periods between grazing events and prescribed fire move this state to the Reference State. This transition may take upwards of 20 years or more to achieve.

Conservation practices

Prescribed Burning
Prescribed Grazing

Transition T2A
State 2 to 3

Heavy, continuous grazing without adequate recovery periods between grazing events and lack of fire shift this state to the Eroded State.

Additional community tables

Table 6. Community 1.1 plant community composition

Group	Common name	Symbol	Scientific name	Annual production (kg/hectare)	Foliar cover (%)
Grass/Grasslike
1				471–538
	sideoats grama	BOCU	Bouteloua curtipendula	135–168	–
	New Mexico feathergrass	HENE5	Hesperostipa neomexicana	101–135	–
	little bluestem	SCSC	Schizachyrium scoparium	101–135	–
	blue grama	BOGR2	Bouteloua gracilis	67–101	–
	James' galleta	PLJA	Pleuraphis jamesii	22–45	–
	western wheatgrass	PASM	Pascopyrum smithii	6–34	–
	switchgrass	PAVI2	Panicum virgatum	0–22	–
	needle and thread	HECOC8	Hesperostipa comata ssp. comata	6–22	–
	green needlegrass	NAVI4	Nassella viridula	6–22	–
	hairy grama	BOHI2	Bouteloua hirsuta	6–22	–
	sun sedge	CAINH2	Carex inops ssp. heliophila	6–22	–
	Grass, perennial	2GP	Grass, perennial	6–22	–
	Indian ricegrass	ACHY	Achnatherum hymenoides	6–22	–
	big bluestem	ANGE	Andropogon gerardii	0–22	–
	plains muhly	MUCU3	Muhlenbergia cuspidata	6–11	–
	ring muhly	MUTO2	Muhlenbergia torreyi	0–6	–
	little barley	HOPU	Hordeum pusillum	0–6	–
	prairie Junegrass	KOMA	Koeleria macrantha	0–6	–
	pinyon ricegrass	PIFI	Piptochaetium fimbriatum	0–6	–
	sand dropseed	SPCR	Sporobolus cryptandrus	0–6	–
	slim tridens	TRMUE	Tridens muticus var. elongatus	0–6	–
	Fendler's threeawn	ARPUF	Aristida purpurea var. fendleriana	0–6	–
	prairie sandreed	CALO	Calamovilfa longifolia	0–6	–
	squirreltail	ELELE	Elymus elymoides ssp. elymoides	0–6	–
	hairy woollygrass	ERPI5	Erioneuron pilosum	0–6	–
	threadleaf sedge	CAFI	Carex filifolia	0–6	–
	black grama	BOER4	Bouteloua eriopoda	0–6	–
Forb
2				67–101
	Forb, perennial	2FP	Forb, perennial	6–22	–
	Forb, perennial	2FP	Forb, perennial	6–22	–
	dotted blazing star	LIPU	Liatris punctata	6–11	–
	purple prairie clover	DAPU5	Dalea purpurea	6–11	–
	American vetch	VIAM	Vicia americana	6–11	–
	dotted blazing star	LIPU	Liatris punctata	6–11	–
	purple prairie clover	DAPU5	Dalea purpurea	6–11	–
	American vetch	VIAM	Vicia americana	6–11	–
	Rocky Mountain zinnia	ZIGR	Zinnia grandiflora	0–6	–
	sulphur-flower buckwheat	ERUM	Eriogonum umbellatum	0–6	–
	hairy false goldenaster	HEVI4	Heterotheca villosa	0–6	–
	tenpetal blazingstar	MEDE2	Mentzelia decapetala	0–6	–
	plains blackfoot	MELE2	Melampodium leucanthum	0–6	–
	crownleaf evening primrose	OECO2	Oenothera coronopifolia	0–6	–
	leafy false goldenweed	OOFOF	Oonopsis foliosa var. foliosa	0–6	–
	white locoweed	OXSE	Oxytropis sericea	0–6	–
	broadbeard beardtongue	PEAN4	Penstemon angustifolius	0–6	–
	spiny phlox	PHHO	Phlox hoodii	0–6	–
	slimflower scurfpea	PSTE5	Psoralidium tenuiflorum	0–6	–
	upright prairie coneflower	RACO3	Ratibida columnifera	0–6	–
	scarlet globemallow	SPCO	Sphaeralcea coccinea	0–6	–
	desert princesplume	STPIP	Stanleya pinnata var. pinnata	0–6	–
	Cuman ragweed	AMPS	Ambrosia psilostachya	0–6	–
	tarragon	ARDR4	Artemisia dracunculus	0–6	–
	white sagebrush	ARLU	Artemisia ludoviciana	0–6	–
	spiny milkvetch	ASKE	Astragalus kentrophyta	0–6	–
	woolly locoweed	ASMO7	Astragalus mollissimus	0–6	–
	Indian paintbrush	CASTI2	Castilleja	0–6	–
	James' cryptantha	CRCIJ	Cryptantha cinerea var. jamesii	0–6	–
	Rocky Mountain zinnia	ZIGR	Zinnia grandiflora	0–6	–
	sulphur-flower buckwheat	ERUM	Eriogonum umbellatum	0–6	–
	hairy false goldenaster	HEVI4	Heterotheca villosa	0–6	–
	tenpetal blazingstar	MEDE2	Mentzelia decapetala	0–6	–
	plains blackfoot	MELE2	Melampodium leucanthum	0–6	–
	crownleaf evening primrose	OECO2	Oenothera coronopifolia	0–6	–
	leafy false goldenweed	OOFOF	Oonopsis foliosa var. foliosa	0–6	–
	white locoweed	OXSE	Oxytropis sericea	0–6	–
	broadbeard beardtongue	PEAN4	Penstemon angustifolius	0–6	–
	spiny phlox	PHHO	Phlox hoodii	0–6	–
	slimflower scurfpea	PSTE5	Psoralidium tenuiflorum	0–6	–
	upright prairie coneflower	RACO3	Ratibida columnifera	0–6	–
	scarlet globemallow	SPCO	Sphaeralcea coccinea	0–6	–
	desert princesplume	STPIP	Stanleya pinnata var. pinnata	0–6	–
	Cuman ragweed	AMPS	Ambrosia psilostachya	0–6	–
	tarragon	ARDR4	Artemisia dracunculus	0–6	–
	white sagebrush	ARLU	Artemisia ludoviciana	0–6	–
	spiny milkvetch	ASKE	Astragalus kentrophyta	0–6	–
	woolly locoweed	ASMO7	Astragalus mollissimus	0–6	–
	Indian paintbrush	CASTI2	Castilleja	0–6	–
	James' cryptantha	CRCIJ	Cryptantha cinerea var. jamesii	0–6	–
Shrub/Vine
3				67–101
	Bigelow sage	ARBI3	Artemisia bigelovii	22–45	–
	James' seaheath	FRJA	Frankenia jamesii	6–22	–
	winterfat	KRLA2	Krascheninnikovia lanata	6–22	–
	Shrub (>.5m)	2SHRUB	Shrub (>.5m)	6–22	–
	fourwing saltbush	ATCA2	Atriplex canescens	6–22	–
	alderleaf mountain mahogany	CEMO2	Cercocarpus montanus	0–11	–
	skunkbush sumac	RHTR	Rhus trilobata	0–11	–
	wax currant	RICE	Ribes cereum	0–11	–
	soapweed yucca	YUGL	Yucca glauca	0–6	–
	golden currant	RIAU	Ribes aureum	0–6	–
	plains pricklypear	OPPO	Opuntia polyacantha	0–6	–
	broom snakeweed	GUSA2	Gutierrezia sarothrae	0–6	–
	prairie sagewort	ARFR4	Artemisia frigida	0–6	–
	tree cholla	CYIMI	Cylindropuntia imbricata var. imbricata	0–6	–
	rubber rabbitbrush	ERNAG	Ericameria nauseosa ssp. nauseosa var. glabrata	0–6	–
Tree
4				0–6
	oneseed juniper	JUMO	Juniperus monosperma	0–6	–
	twoneedle pinyon	PIED	Pinus edulis	0–6	–

Interpretations

Animal community

WILDLIFE INTERPRETATIONS:
The loamy soils and grasses, forbs, and shrubs found on this ecological site provides habitat for numerous wildlife species. Historic large grazers that influenced these plant communities were bison, elk, and pronghorn. Changes over time have resulted in the loss of bison, the reduction in elk numbers, and pronghorn population swings. Domestic grazers now share these habitats with wildlife. The grassland communities of eastern Colorado are home to many bird species. Changes in the composition of the plant community when moving from the reference plant community to other communities on this ecological site may result in species shifts in the bird community. The occasional wetland or spring found on this ecological site provides essential seasonal water needed for reproductive habitat by some reptiles and amphibians. Because of a lack of permanent water, fish are not commonly expected on this ecological site. Mule and white-tailed deer may use this ecological site. The gray wolf and wild bison used this ecological site in historic times. The wolf is thought to be extirpated from Eastern Colorado Bison are currently found only as domestic livestock.

Reference Plant Community:
The grasses, forbs, and shrubs in this plant community provide habitat for many reptiles including western rattlesnake, bullsnake, and racer. If water is available for breeding, spadefoot toads and tiger salamanders may be found here. The structural diversity in the plant community on this site provides habitat for Cassin’s sparrow and lark bunting. Ferruginous and Swainson’s hawks are commonly seen on this site. Small mammals such as white-tailed jackrabbit, badger, swift fox, plains pocket gopher, and several species of mice are common. Pronghorn is a typical ungulate.

1.2 Community:
All wildlife found in the reference plant community are expected in this plant community. The loss of some of the vegetative structural diversity makes it less attractive to some species.

1.3, 2.1, 3.1 Communities:
Reptiles using these plant communities are similar to the reference community species. As bare ground increases, conditions improve for Texas horned lizard. Increases in broom snakeweed and small soapweed cause the bird community to shift from Cassin’s sparrow to the grasshopper sparrow. Most mammals will be similar to the reference plant community, however black-tailed jackrabbit use may increase because of the increased bare ground and weedy forbs.

GRAZING INTERPRETATIONS:
The following table lists suggested initial stocking rates for an animal unit (1000 pound beef cow) under continuous grazing (yearlong grazing or growing-season-long grazing) based on normal growing conditions. However, continuous grazing is not recommended. These estimates should only be used as preliminary guidelines in the initial stages of the conservation planning process. Often, the existing plant composition does not entirely match any particular plant community described in this ecological site description. Therefore, field inventories are always recommended to document plant composition, total production, and palatable forage production. Carrying capacity estimates that reflect on-site conditions should be calculated using field inventories.

If the following production estimates are used, they should be adjusted based on animal kind or class and on the specific palatability of the forage plants in the various plant community descriptions. Under a properly stocked, properly applied, prescribed grazing management system that provides adequate recovery periods following each grazing event, improved harvest efficiencies eventually result in increased carrying capacity. See USDA-NRCS Colorado Prescribed Grazing Standard and Specification Guide (528).

The stocking rate calculations are based on the total annual forage production in a normal year multiplied by 25 percent harvest efficiency divided by 912.5 pounds of ingested air-dry vegetation for an animal unit per month (AUM).

Plant Community Production (lbs./acre) and Stocking Rate (AUM/acre)

(Reference Plant Community) - (600) (0.16)

1.2 Community - (300) (0.08)

These stocking rates are guidelines and grazing plans should be developed from an on-site visit.

Grazing by domestic livestock is one of the major income-producing industries in the area. Rangelands in this area provide yearlong forage under prescribed grazing for cattle, sheep, horses, and other herbivores.

Hydrological functions

Water is the principal factor limiting forage production on this site. This site is dominated by soils in hydrologic group B, with localized areas in hydrologic group A. Infiltration is moderate to high and runoff potential for this site is moderate depending on soil hydrologic group and ground cover. Areas where ground cover is less than 50 percent have the greatest potential to have reduced infiltration and higher runoff (refer to NRCS Section 4, National Engineering Handbook (NEH-4) for runoff quantities and hydrologic curves).

Recreational uses

This site provides hunting, hiking, photography, bird watching, and other opportunities. The wide varieties of plants that bloom from spring until fall have an aesthetic value that appeals to visitors.

Wood products

Fence posts or fire wood from juniper and pinyon trees.

Other products

This site is commonly mined for the production of cement in Fremont and Pueblo counties.

General Data (MLRA and Revision Notes, Hierarchical Classification, Ecological Site Concept, Physiographic, Climate, and Water Features, and Soils Data):Updated. All “Required” items are complete to Provisional level.

Community Phase Data (Ecological Dynamics, STM, Transition and Recovery Pathways, Reference Plant Community, Species Composition List, Annual Production Table):

Updated. All “Required” items are complete to Provisional level.

LRU Concepts are still being debated. Further refinement of LRU concepts should be revisited with the technical team at the next “Approved” level.

Further discussion is needed to determine whether a “Shallow Limestone” site (lesser slopes) needs to be developed. There is currently a broad slope range (0 to 45 percent) in the existing “Limestone Breaks” site.

Community Phase Data (Ecological Dynamics, STM, Transition and Recovery Pathways, Reference Plant Community, Species Composition List, Annual Production Table):

There has been discussion that the Blue Grama Dominated State/Plant Community belongs in the Reference State, if grazing management will restore this community. However, the site authors feel that this should remain a separate state in MLRA 69 due to the lower precipitation, higher evapotranspiration rates, and in this case, shallow soils. It is felt that this restoration cannot be achieved within a 40 year planning horizon.

It is likely the "Low Plant Density, Decadent Plant Community exists on steeper and less accessible slopes. This is due to increased plant decadence (not excessive litter accumulation). The current concept is to leave this community in, but the topic needs future discussion.

NOTE: Annual Production Table and Species Composition List are from the “Previously Approved ESD. These will need review for future updates at the next Approved level.

Each Alternative State/Community:

-Complete to Provisional level. Narrative for each state/community has been updated.

Supporting Information (Site Interpretations, Associated and Similar Sites, Inventory Data References, Agency/State Correlation, References):

Updated. All “Required” items complete to Provisional level.

Supporting Information:

Updated. All “Required” items complete to Provisional level.

Animal Community Wildlife Interpretations:First “overview” paragraph retained.
Individual Plant Community phase interpretations are removed and need to be updated at next “Approved” level.

Livestock Interpretations:
Updated to reflect the plant community name revisions. The Stocking rate calculations remain the same because they are based on the “Legacy” Total Annual Production table.
The stocking rate calculations need to be updated when Total Annual Production and Plant Community annual production is revised at the next “Approved” level.

Hydrology:
From “Previously Approved” ESD (2004). This needs to be updated at next “approved” level.

Other Site Interpretation:
Recreational Uses, Wood Products, Other Products, and Plant Preferences table, and Rangeland Health Reference Sheet carried over from “Previously Approved” ESD (2004).

Rangeland Health Reference Sheet:
From “Previously Approved” ESD (2004). This needs to be updated at the “Approved” level.

LRU C Limestone Breaks ESD will be developed at a future date.

“Future work, as described in a project plan, to validate the information in this provisional ecological site description is needed. This will include field activities to collect low and medium intensity sampling, soil correlations, and analysis of that data. Annual field reviews should be done by soil scientists and vegetation specialists. A final field review, peer review, quality control, and quality assurance reviews of the ESD will be needed to produce the final document.” (NI 430_306 ESI and ESD, April, 2015)

Other information

Relationship to Other Classifications:
NRCS Classification Hierarchy:
Physiographic Divisions of the United States (Fenneman, 1946): Physiographic DivisionPhysiographic ProvincePhysiographic SectionLand Resource RegionMajor Land Resource Area (MLRA)Land Resource Unit (LRU).

USFS Classification Hierarchy:
National Hierarchical Framework of Ecological Units (Cleland et al, 181-200):
DomainDivisionProvinceSectionSubsectionLandtype Association LandtypeLandtype Phase.

Supporting information

Inventory data references

NRI: references to Natural Resource Inventory data
Information presented here has been derived from data collection on private and federal lands using:
• Double Sampling (clipped 2 of 5 plots)*
• Rangeland Health (Pellant et al., 2005)
• Soil Stability (Pellant et al., 2005)
• Line Point Intercept : Foliar canopy, basal cover (Forb, Graminoid, Shrub, subshrub, Lichen, Moss, Rock fragments, bare ground, % Litter) (Herrick et al., 2005)
• Soil pedon descriptions collected on site (Schoeneberger et al., 2012)

*NRCS double-sampling method, CO NRCS Similarity Index Worksheet 528(1).
Additional reconnaissance data collection using numerous ocular estimates and other inventory data; NRCS clipping data for USDA program support; Field observations from experienced range trained personnel. Specific data information is contained in individual landowner/user case files and other files located in county NRCS field offices.

References

Guyette, R.P., M.C. Stambaugh, D.C. Dey, and R. Muzika. 2012. Predicting Fire Frequency with Chemistry and Climate. Ecosystems 15:322–335.

Other references

Data collection for this ecological site was done in conjunction with the progressive soil surveys within the Upper Arkansas Valley (MLRA 69) of Colorado. The site has been mapped and correlated with soils in the following soil surveys: Baca County, Bent County, Crowley County, El Paso County Area, Fremont County Area, Huerfano County Area, Kiowa County, Las Animas County: Parts of Huerfano and Las Animas, Lincoln County, Otero County, Prowers County, and Pueblo Area: Parts of Pueblo and Custer Counties.

30 Year Climatic and Hydrologic Normals (1981-2010) Reports. National Water and climate Center: Portland, OR. August 2015

ACIS-USDA Field Office Climate Data (WETS), period of record 1971-2000 http://agacis.rcc-acis.org (powered by WRCC) Accessed March 2016

Andrews, R. and R. Righter. 1992. Colorado Birds. Denver Museum of Natural History, Denver, CO. 442

Armstrong, D.M. 1972. Distribution of mammals in Colorado. Univ. Kansas Museum Natural History Monograph #3. 415.

Butler, LD., J.B. Cropper, R.H. Johnson, A.J. Norman, G.L. Peacock, P.L. Shaver, and K.E. Spaeth. 1997, revised 2003. National Range and Pasture Handbook. National Cartography and Geospatial Center’s Technical Publishing Team: Fort Worth, TX. http://www.glti.nrcs.usda.gov/technical/publications/nrph.html Accessed August 2015

Clark, J., E. Grimm, J. Donovan, S. Fritz, D. Engrstom, and J. Almendinger. 2002. Drought cycles and landscape responses to past Aridity on prairies of the Northern Great Plains, USA. Ecology, 83(3), 595-601.

Cleland, D., P. Avers, W.H. McNab, M. Jensen, R. Bailey, T. King, and W. Russell. 1997. National Hierarchical Framework of Ecological Units, published in Ecosystem Management: Applications for Sustainable Forest and Wildlife Resources, Yale University Press

Cooperative climatological data summaries. NOAA. Western Regional Climate Center: Reno, NV. Web. http://www.wrcc.dri.edu/climatedata/climsum Accessed August 2015

Egan, Timothy. 2006. The Worst Hard Time. Houghton Mifflin Harcourt Publishing Company: New York, NY.

Fitzgerald, J.P., C.A. Meaney, and D.M. Armstrong. 1994. Mammals of Colorado. Denver Museum of Natural History, Denver, CO. 467. Hammerson, G.A. 1986. Amphibians and reptiles in Colorado. CO Div. Wild. Publication Code DOW-M-I-3-86. 131.

Herrick, Jeffrey E., J.W. Van Zee, K.M. Haystad, L.M. Burkett, and W.G. Witford. 2005. Monitoring Manual for Grassland, Shrubland, and Savanna Ecosystems, Volume II. U.S. Dept. of Agriculture, Agricultural Research Service. Jornada Experimental Range, Las Cruces, N.M.

Kingery, H., Ed. (1998) Colorado Breeding Birds Atlas. Dist. CO Wildlife Heritage Foundation: Denver, CO. 636.

National Water & Climate Center. USDA-NRCS. USDA Pacific Northwest Climate Hub: Portland, OR. http://www.wcc.nrcs.usda.gov/ Accessed March 2016

National Weather Service Co-op Program. 2010. Colorado Climate Center. Colorado State Univ. Web. http://climate.atmos.colostate.edu/dataaccess.php March 2016

Pellant, M., P. Shaver, D.A. Pyke, J.E. Herrick. (2005) Interpreting Indicators of Rangeland Health, Version 4. BLM National Business Center Printed Materials Distribution Service: Denver, CO.

PLANTS Database. 2015. USDA-NRCS. Web. http://plants.usda.gov/java/ Accessed August 2015. February 2016

PRISM Climate Data. 2015. Prism Climate Group. Oregon State Univ. Corvallis, OR. http://www.prism.oregonstate.edu/ Accessed August 2015.

Rennicke, J. 1990. Colorado Wildlife. Falcon Press, Helena and Billings, MT and CO Div. Wildlife, Denver CO. 138.

Schoeneberger, P.J., D.A. Wysockie, E.C. Benham, and Soil Survey Staff. 2012. Field book for describing and sampling soils, Version 3.0. Natural Resources Conservation Service, National Soil Survey Center: Lincoln, NE.

The Denver Posse of Westerners. 1999. The Cherokee Trail: Bent’s Old Fort to Fort Bridger. The Denver Posse of Westerners, Inc. Johnson Printing: Boulder, CO

U.S. Dept. of Agriculture, Agricultural Research Service. September, 1991. Changes in Vegetation and Land Use I eastern Colorado, A Photographic study, 1904-1986.

U.S. Dept. of Agriculture, Natural Resources Conservation Service. 2006. Land Resource Regions and Major Land Resource areas of the United States, the Caribbean, and the Pacific Basin. US Department of Agriculture Handbook 296.

U.S. Dept. of Agriculture, Natural Resources Conservation Service. National Geospatial Center of Excellence. Colorado annual Precipitation Map from 1981-2010, Annual Average Precipitation by State

U.S. Dept. of Agriculture, Natural Resources Conservation Service. 2009. Part 630, Hydrology, National Engineering Handbook

U.S. Dept. of Agriculture, Natural Resources Conservation Service. 1972-2012. National Engineering Handbook Hydrology Chapters. http://www.nrcs.usda.gov/wps/portal/nrcs/detailfull/national/water/?&cid=stelprdb1043063 Accessed August 2015.

U.S. Dept. of Agriculture, Natural Resources Conservation Service. National Soil Survey Handbook title 430-VI. http://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/ref/?cid=nrcs142p2_054242 Accessed July 2015

U.S. Dept. of Agriculture, Soil Survey Division Staff. 1993. Soil Survey Manual.

U.S. Dept. of Agriculture.1973. Soil Survey of Baca County, Colorado.

U.S. Dept. of Agriculture. 1970. Soil Survey of Bent County, Colorado.

U.S. Dept. of Agriculture. 1968. Soil Survey of Crowley County, Colorado.

U.S. Dept. of Agriculture. 1981 Soil Survey of El Paso County Area, Colorado.

U.S. Dept. of Agriculture. 1995. Soil Survey of Fremont County Area, Colorado.

U.S. Dept. of Agriculture. 1983. Soil Survey of Huerfano County Area, Colorado.

U.S. Dept. of Agriculture.1981. Soil Survey of Kiowa County, Colorado.

Western Regional Climate Center. 2022. Climate of Colorado, climate of the eastern plains. https://wrcc.dri.edu/Climate/narrative_co.php (accessed 9 August 2022).

Contributors

Doug Whisenhunt Ecological Site Specialist NRCS
Laura L. Craven MLRA Project Leader NRCS
Ben P. Berlinger Rangeland Management Specialist NRCS Retired
Kimberly A. Diller Ecological Site Specialist NRCS

Approval

Kirt Walstad, 4/30/2024

Acknowledgments

Project Staff:
Kimberly Diller, Ecological Site Specialist, NRCS MLRA, Pueblo Soil Survey Office (SSO)
Laura Craven, MLRA 69 Soil Survey Leader, NRCS MLRA Pueblo SSO
Amber Wyndham, Soil Scientist, NRCS MLRA Pueblo SSO
Ben Berlinger, Rangeland Management Specialist, Ret. NRCS La Junta, CO

Program Support:
Rachel Murph, NRCS State Rangeland Management Specialist
David Kraft, NRCS MLRA Ecological Site Specialist-QA (acting), Emporia, KS
Chad Remley, Regional Director, N. Great Plains Soil Survey, Salina, KS
B.J. Shoup, State Soil Scientist, Denver
Eugene Backhaus, State Resource Conservationist, Denver
Chanda Garcia, NRCS State Biologist, NRCS, Denver CO
Patty Knupp, Area 3 Biologist, NRCS, Pueblo CO

Partners/Contributors:
James Kulbeth, Natural Resources Specialist, Department of the Army, Fort Carson, CO
John Lamman, Rangeland Management Specialist, BLM, Cañon City, CO
Steve Olson, Botanist, USFS, Pueblo, CO
Renee Rondeau, Ecologist, CO Natural Heritage Program, Hesperus, CO
Terri Schultz, The Nature Conservancy, Ft. Collins, CO
John Valentine, District Manager, CO State Land Board, Pueblo, CO

Those involved in developing earlier versions of this site description include: Ben Berlinger, rangeland management specialist (RMS); Scott Woodall, RMS; Lee Neve, soil scientist; Julie Elliott, RMS; Terri Skadeland, Colorado State biologist; and Herman Garcia, Colorado State RMS.

Rangeland health reference sheet

Interpreting Indicators of Rangeland Health is a qualitative assessment protocol used to determine ecosystem condition based on benchmark characteristics described in the Reference Sheet. A suite of 17 (or more) indicators are typically considered in an assessment. The ecological site(s) representative of an assessment location must be known prior to applying the protocol and must be verified based on soils and climate. Current plant community cannot be used to identify the ecological site.

Author(s)/participant(s)	Ben Berlinger, Daniel Nosal, Kimberly Diller
Contact for lead author	Ben Berlinger, Area Rangeland Management Specialist, La Junta, CO,
Date	01/12/2005
Approved by	Kirt Walstad
Approval date
Composition (Indicators 10 and 12) based on	Annual Production