Natural Resources
Conservation Service
Ecological site R066XY066NE
Loamy Terrace
Last updated: 11/18/2024
Accessed: 11/21/2024
General information
Approved. An approved ecological site description has undergone quality control and quality assurance review. It contains a working state and transition model, enough information to identify the ecological site, and full documentation for all ecosystem states contained in the state and transition model.
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): 066X–Dakota-Nebraska Eroded Tableland
The Dakota-Nebraska Eroded Tableland (MLRA 66) is divided almost evenly between north-central Nebraska (56 percent) and south-central South Dakota (44 percent). MLRA 66 is approximately 3.6 million acres and covers all or parts of 12 counties between the two states. The northern border of the MRLA bisects Tripp County, South Dakota, just south of the town of Winner. Valentine is in the northeastern corner of Cherry County, Nebraska and is located on the MLRA’s southwestern border. From there, the MLRA stretches southeast to the northwestern corner of Antelope County, Nebraska and the town of O’Neil, Nebraska in Holt County its southeastern border.
The MLRA occupies a smooth fluvial plain primarily consisting of broad intervalley areas that have terraces, river breaks, and local badlands along the well-defined major drainages. The slopes range from nearly level tablelands to steep ridges and drainages. The elevation ranges from 1,970 to 2,950 feet. The Keya Paha, Elkhorn, and the Niobrara Rivers flow through the MLRA. The Niobrara is a designated National Scenic River.
Layers of shaly chalk and limestone marine sediments overlaying the Cretaceous Niobrara Formation make up the bulk of the MLRA, though the western and southwestern portions exhibit surface eolian deposits. The floors of the major drainages are underlain by deposits of alluvial sand and gravel. The dominant soil orders in this MLRA are mesic, ustic or aridic Mollisols and Entisols. Loamy and sandy are the primary soil textures in this landscape.
Twenty-seven percent of the land in this MLRA has been broken out of native prairie and farmed, while 66 percent of the grasslands remain intact. The remaining acres are divided between forest, urban development, and other uses. Livestock grazing, primarily by cattle, is a major industry. Corn, winter wheat, and grain sorghum are the primary commodity crops but a significant number of acres are planted to forage sorghum and alfalfa for harvest as hay. With limited irrigation available, and annual precipitation averaging from 18 inches in the west to 25 inches in the east, crop production is marginal across most of the MLRA.
The historical matrix vegetation type is mixed-grass prairie. Bluestems, prairie sandreed, sideoats grama, and blue grama make up the bulk of the warm-season species. Western wheatgrass, green needlegrass, and needle and thread are the dominant cool-season grasses. Large- and small-patch vegetative communities are primarily along the riparian zones, on lowland sites, and in closed depressions. Woodlands make up about 3 percent of MLRA 66 and consist primarily of green ash, bur oak, and hackberry. Ponderosa pines can be found on some steeper sites in the western portion of the landscape.
Wildlife flourishes in this combination of crop and grassland environments. In a landscape historically occupied by bison herds, white-tailed and mule deer are now the most abundant wild ungulates. Pronghorns also number among the remaining native grazers. A variety of smaller species, including coyote, raccoon, opossum, porcupines, muskrat, beaver, squirrel, prairie dogs, and mink, thrive in the region. Grassland birds, including several upland game birds, are common across the MLRA.
This landscape serves as a backdrop for a disturbance-driven ecosystem, evolving under the influences of herbivory, fire, and variable climate. Historically, these processes created a heterogeneous mosaic of plant communities and structure heights across the region. Any given site in this landscape burned every six to ten years, with most of the MLRA experiencing a six to eight year fire regime. The fires were caused by lightning strikes and were also set by Native Americans, who used fire for warfare, signaling, and to refresh the native grasses. Indigenous inhabitants understood the value of fire as a tool, and that the highly palatable growth following a fire provided excellent forage for their horses and attracted grazing game animals such as bison and elk.
Land use patterns by post-European settlers have greatly altered the historical fire regime, allowing the expansion of woody species. Fragmentation of the native grasslands by conversion to cropland, transportation corridors, and other developments has contributed to disruption of the natural fire regime of this ecosystem. The most common encroaching woody species is eastern redcedar. While eastern redcedar is native to the landscape, the historic population in MLRA 66 was limited to isolated pockets in rugged river drainageways that were protected from wildfire. Widespread plantings of windbreaks with eastern redcedar as a primary component provide a seed source for the aggressive woody plant which further facilitates woody encroachment. Encroachment of native and introduced shrubs and trees into the native grasslands degrades wildlife habit and causes significant forage loss for domestic livestock. Aggressive fire suppression policies have exacerbated this process to the point that shrub and tree encroachment is a major ecological threat to grasslands throughout most of the MLRA.
Classification relationships
►EPA◄
Level IV Ecoregions of the Conterminous United States
43—Northwestern Great Plains:
43i—Keya Paha Tablelands.
►USDA◄
Land Resource Regions and Major Land Resource Areas (USDA-NRCS, 2006)
Land Resource Region: G—Western Great Plains Range and Irrigated Region:
Major Land Resource Area (MLRA): 66 Dakota-Nebraska Eroded Tableland.
Ecological site concept
The Loamy Terrace ecological site is found on elevated terrace positions directly above the floodplain and located adjacent to loamy and loamy overflow ecological sites. This site does not typically receive moisture from overflow but does receive run-off from adjacent upland sites. Slopes typically range from 0 to 2 percent. Soils are very deep, moderately well to well drained soils formed in alluvium. Surface textures silt loam, silty clay loam, or loam.
The historical native vegetation is Mixed Grass Prairie. The vegetation in the Reference Plant Community (1.1) is dominated by cool-season grasses with warm-season grasses subdominant. Primary grasses include green needlegrass and western wheatgrass. Other important grasses include Canada wildrye, slender wheatgrass, and big bluestem. Forbs are common and diverse. Shrubs include western snowberry, leadplant, and rose. The site is susceptible to invasion of non-native, cool-season grasses, especially Kentucky bluegrass and smooth brome.
Associated sites
R066XY036NE |
Loamy 18-22 P.Z. The Loamy 18-22 PZ ecological sites often occur adjacent to Loamy Terrace ecological sites but occupy a higher landscape position. |
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R066XY059NE |
Thin Upland The Loamy 22-25 PZ ecological sites often occur adjacent to Loamy Terrace ecological sites but occupy a higher landscape position. |
R066XY046NE |
Subirrigated Subirrigated ecological sites often occur in proximity to the Loamy Terrace ecological sites but occupy a slightly lower landscape position. |
R066XY026NE |
Loamy Overflow Loamy Overflow ecological sites often occur in proximity to the Loamy Terrace ecological sites but occupy a slightly lower landscape position. |
Similar sites
R066XY026NE |
Loamy Overflow The Loamy Overflow and Loamy Terrace ecological sites occurs on similar soils and have similar slopes but Loamy Overflow sites are found on active floodplains and experience rare to frequent flooding while the Loamy Terrace sites are not found on active floodplains and are typically do not experience flooding. |
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Table 1. Dominant plant species
Tree |
Not specified |
---|---|
Shrub |
Not specified |
Herbaceous |
(1) Pascopyrum smithii |
Physiographic features
The Loamy Terrace ecological site occurs on nearly level to gently sloping areas along drainageways of uplands and in valleys. This site receives run-in water from areas higher on the landscape. The site typically does not experience flooding but some sites occasionally flood for brief periods of time.
Figure 2. Block diagram
Table 2. Representative physiographic features
Landforms |
(1)
Valley
> Flood plain
(2) Stream terrace |
---|---|
Runoff class | Negligible to low |
Flooding duration | Brief (2 to 7 days) |
Flooding frequency | None to occasional |
Ponding frequency | None |
Elevation | 579 – 914 m |
Slope | 0 – 2% |
Water table depth | 152 – 203 cm |
Aspect | Aspect is not a significant factor |
Climatic features
MLRA 66 is considered to have a continental climate with cold winters and hot summers, low humidity, light rainfall, and much sunshine. Extremes in temperature may also abound. The climate is the result of this MLRA’s location near the geographic center of North America. There are few natural barriers on the northern Great Plains and the winds move freely across the plains and account for rapid changes in temperature.
Annual precipitation ranges from 18 to 25 inches per year. The normal average annual temperature is about 48°F. January is the coldest month with average temperatures ranging from about 19°F (Bonesteel, SD) to about 23°F (Ainsworth, NE). July is the warmest month with temperatures averaging from about 73°F (Harrington, SD) to about 75°F (Gregory, SD). The range of normal average monthly temperatures between the coldest and warmest months is about 54°F. This large annual range attests to the continental nature of the climate this area. Hourly winds average about ten miles per hour annually, ranging from about 11 miles per hour during the spring to about nine miles per hour during the summer. Daytime winds are generally stronger than nighttime and occasional strong storms may bring brief periods of high winds with gusts to more than 50 miles per hour.
Growth of native cool-season plants begins mid to late March and continues to late June. Native warm-season plants begin growth in early May and continue to late August. Green-up of cool-season plants may occur in September and October when adequate soil moisture is present.
Table 3. Representative climatic features
Frost-free period (characteristic range) | 116-125 days |
---|---|
Freeze-free period (characteristic range) | 136-141 days |
Precipitation total (characteristic range) | 610-660 mm |
Frost-free period (actual range) | 114-128 days |
Freeze-free period (actual range) | 136-142 days |
Precipitation total (actual range) | 610-686 mm |
Frost-free period (average) | 120 days |
Freeze-free period (average) | 139 days |
Precipitation total (average) | 635 mm |
Figure 3. Monthly precipitation range
Figure 4. Monthly minimum temperature range
Figure 5. Monthly maximum temperature range
Figure 6. Monthly average minimum and maximum temperature
Figure 7. Annual precipitation pattern
Figure 8. Annual average temperature pattern
Climate stations used
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(1) BUTTE [USC00251365], Butte, NE
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(2) FAIRFAX #2 [USC00392822], Fairfax, SD
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(3) SPRINGVIEW [USC00258090], Springview, NE
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(4) GREGORY [USC00393452], Gregory, SD
Influencing water features
No significant water features influence this site.
Soil features
The soil series associated with the Loamy Terrace ecological site are very deep, moderately well to well drained, moderately permeable soils formed in alluvium. These valley and low terrace soils have slopes typically ranging from 0 to 2 percent.
This site should show no evidence of rills, wind scoured areas, or pedestalled plants. Water flow paths are broken, irregular in appearance or discontinuous with numerous debris dams or vegetative barriers. The soil surface is stable and intact. These soils are mainly susceptible to water erosion. The hazard of water erosion increases where vegetative cover is not adequate. A drastic loss of the soil surface layer on this site can result in a shift in species composition and production.
Big Bend, Shell, Grigston, Bridgeport, Brocksburg, Hall, Haynie, and Nimbro are the major soil series correlated to the Loamy Terrace ecological site. More information can be found in the various soil survey reports. Contact the local USDA Service Center for soil survey reports that include more detail specific to your location or visit Web Soil Survey (https://websoilsurvey.sc.egov.usda.gov).
Figure 9. Shell Series profile
Table 4. Representative soil features
Parent material |
(1)
Alluvium
|
---|---|
Surface texture |
(1) Silt loam (2) Silty clay loam (3) Loam |
Family particle size |
(1) Loamy |
Drainage class | Moderately well drained to well drained |
Permeability class | Moderately slow to moderate |
Soil depth | 152 – 203 cm |
Surface fragment cover <=3" | 0 – 3% |
Surface fragment cover >3" | 0% |
Available water capacity (Depth not specified) |
14.73 – 23.11 cm |
Calcium carbonate equivalent (Depth not specified) |
0 – 30% |
Electrical conductivity (Depth not specified) |
0 – 2 mmhos/cm |
Sodium adsorption ratio (Depth not specified) |
0 – 10 |
Soil reaction (1:1 water) (Depth not specified) |
5.6 – 8.4 |
Subsurface fragment volume <=3" (Depth not specified) |
0 – 19% |
Subsurface fragment volume >3" (Depth not specified) |
0% |
Ecological dynamics
Loamy Terrace ecological sites developed under Northern Great Plains climatic conditions, light to severe grazing by bison and other large herbivores, sporadic natural or man-caused wildfire, and other biotic and abiotic factors that typically influence soil and site development. Herbivory, fire, and variable climate are the primary disturbances that impact the grassland ecological dynamics of the site. Changes occur in the plant communities due to short-term weather variations, impacts of native and exotic plant and animal species, and management actions.
One of the primary impacts to the native rangeland remnants of this site introduced by European settlers is season-long, continuous grazing by domestic livestock. This management practice causes the repeated removal of the growing point and excessive defoliation of the leaf area of individual warm-season tallgrasses. The resulting reduction of the ability of the plants to harvest sunlight depletes the root reserves, subsequently decreasing the root mass. This negatively impacts the ability of the plants to compete for life-sustaining nutrients, resulting in declining vigor and eventual mortality. The space created in the vegetative community is then occupied by a species that evades the negative grazing impacts by a growing season adaptation (such as a cool-season), a shorter structure, growing points which do not elevate but which remain near the soil surface, or reduced palatability.
A high percentage of these areas have been farmed and planted to alfalfa for haying or commodity crops. These sites often occur in areas which provide good wintering grounds for livestock and are used as calving and feeding areas. Areas that have not been tilled typically are or have been continuously hayed resulting in a monoculture of western wheatgrass. Very few areas exist that have not had severe soil disturbance. Grazed areas have often been grazed continuously throughout the growing season which causes this site to eventually transition from the Reference State. Continuous seasonal grazing or heavy rotational grazing with inadequate growing season recovery periods will also cause this transition. Species such as blue grama will initially increase while western wheatgrass, green needlegrass, and sideoats grama will decrease in frequency and production. Extended periods of non-use and lack of fire will result in a plant community having high litter levels, which favors an increase in non-native grasses and over time, shrubs and trees such as western snowberry, chokecherry and green ash.
Interpretations are primarily based on the Reference Community (1.1) which has been determined by study of rangeland relic areas, areas protected from excessive disturbance, and areas under long-term rotational grazing regimes. Trends in plant community dynamics ranging from heavily grazed to lightly grazed areas, seasonal use pastures, and historical accounts have been used as well. Plant communities, states, transitional pathways, and thresholds have been determined through similar studies and experience.
The State and Transition Model (STM) is depicted below and includes a Reference State (1), a Native/Invaded Grass State (2), an Invaded State (3), an Early Seral State (4), and an Invaded Woody State (5), and a Sodbusted State (6). Each state represents the crossing of a major ecological threshold due to the alteration of the functional dynamic properties of the ecosystem. The primary properties observed to determine this change are soil stability, vegetative communities, and the hydrologic cycle. Each state may have one or more plant communities that fluctuate in species composition and abundance within the normal parameters of the state. Within each state, communities may degrade or recover in response to natural and man caused disturbances such as variation in the degree and timing of herbivory, presence or absence of fire, and climatic and local fluctuations in the precipitation regime. The processes that cause the movement between the states and communities are discussed in more detail in the state and community descriptions following the diagram.
State and transition model
Figure 10. State and Transition Model Diagram. MLRA 66, Loamy Terrace Ecological Site.
Figure 11. State and Transition Model Diagram Legend. MLRA 66, Loamy Terrace Ecological Site.
More interactive model formats are also available.
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More interactive model formats are also available.
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Click on state and transition labels to scroll to the respective text
Ecosystem states
States 1, 5 and 6 (additional transitions)
States 2, 5 and 6 (additional transitions)
T1A | - | Invasion of non-native cool-season grasses, long term (>10 years) seasonal grazing in summer, continuous season long grazing, rotational grazing with inadequate growing season recovery periods or non-use with no fire. |
---|---|---|
T2A | - | Long term (> 15 years) severe disturbance or heavy, concentrated, continuous season long grazing or seasonal grazing. |
T1C | - | Woody encroachment with no prescribed burning or woody species management. |
T1D | - | Tillage to facilitate production agriculture. |
R2A | - | Long-term (> 15 years) prescribed grazing during spring or spring and fall. |
T2A | - | Continued invasion of non-native cool-season grasses facilitated by seasonal grazing in summer, continuous season long grazing, rotational grazing with inadequate growing season recovery periods or non-use with no fire. |
T2B | - | Long term (> 15 years) severe disturbance or heavy, concentrated, continuous season long grazing or seasonal grazing. |
T2C | - | Woody encroachment with no prescribed burning or woody species management. |
T2D | - | Tillage to facilitate production agriculture. |
T3A | - | Long term (> 15 years) severe disturbance or heavy, concentrated, continuous season long grazing or seasonal grazing. |
T3B | - | Woody encroachment with no prescribed burning or woody species management. |
T3C | - | Tillage to facilitate production agriculture. |
T4A | - | Woody encroachment with no prescribed burning or woody species management. |
T4B | - | Tillage to facilitate production agriculture. |
R5A | - | Prescribed burning, wildfire, timber harvest, brush management. |
R5B | - | Prescribed burning, wildfire, timber harvest, brush management. |
R5C | - | Prescribed burning, wildfire, timber harvest, brush management. |
R5D | - | Prescribed burning, wildfire, timber harvest, brush management. |
R5E | - | Prescribed burning, wildfire, timber harvest, brush management. |
T6A | - | Woody encroachment with no prescribed burning or woody species management. |
State 1 submodel, plant communities
1.1A | - | Continuous season-long grazing or repetitive haying. |
---|---|---|
1.2A | - | Prescribed grazing with adequate growing season recovery periods. |
State 2 submodel, plant communities
State 3 submodel, plant communities
State 4 submodel, plant communities
State 5 submodel, plant communities
State 6 submodel, plant communities
State 1
Reference State
The Reference State (1) describes the range of vegetative communities that occur on the Loamy Terrace ecological site where the range of natural variability under historic conditions and disturbance regimes is mostly intact. The Reference State developed under the combined influences of climatic conditions, periodic fire activity, grazing by large herbivores, and impacts from small mammals and insects. High perennial grass cover and production allows for increased soil moisture retention, vegetative production and overall soil quality. The Reference State includes three plant community phases which are the Reference Community (1.1) and the At-Risk Community (1.2). The Reference Community serves as a description of the native plant community that occurs on the site when the natural disturbance regimes are intact or closely mimicked by management practices. The At-Risk Community results from management decisions that are unfavorable for a healthy Reference Community.
Dominant plant species
-
western wheatgrass (Pascopyrum smithii), grass
-
slender wheatgrass (Elymus trachycaulus), grass
-
green needlegrass (Nassella viridula), grass
-
big bluestem (Andropogon gerardii), grass
-
blue grama (Bouteloua gracilis), grass
Community 1.1
Reference Community
Interpretations are based primarily on the Reference or Western Wheatgrass-Green Needlegrass (Pascopyrum smithii-Nassella viridula) Community (1.1). This plant community serves as a description of the native plant community that occurs on the site when the natural disturbance regimes are intact or are closely mimicked by management practices. This phase is dynamic, with fluid relative abundance and spatial boundaries between the dominant structural vegetative groups. These fluctuations are primarily driven by different responses of the species to changes in precipitation timing and abundance, and to fire and grazing events. This site developed with grazing by large herbivores and is well suited for grazing by domestic livestock. This community is dominated by cool-season rhizomatous grass and bunchgrass. The major grasses include western wheatgrass and green needlegrass. Other prominent grasses and grass-likes include Canada wildrye, slender wheatgrass, big bluestem, sideoats grama, blue grama, and sedges. Forbs include American licorice, goldenrod, Maximilian sunflower, and white sagebrush. Shrubs include leadplant, American plum, and western snowberry. American elm, bur oak, green ash, or plains cottonwood may be present on the site. The potential vegetation is between 75 to 85 percent grasses or grass-like plants, 5 to 10 percent forbs, 5 to 10 percent shrubs, and 1 to 5 percent trees. Natural fire played a significant role in the succession of this site by limiting the extent of eastern redcedar. Wildfires have been actively controlled in recent times, allowing eastern redcedar encroachment. This plant community can be found on areas that are managed with prescribed grazing, prescribed burning, and may be found on areas receiving occasional periods of short-term rest. This resilient community is well adapted to the Northern Great Plains climatic conditions. This community is drought tolerant due to high plant species diversity and the resulting varied root structures. Individual species can vary greatly in production depending on the timing and amount of precipitation, and temperature fluctuations. Plant diversity promotes strong tolerance to drought, site and soil stability, a functional hydrologic cycle, a high degree of biotic integrity, and high soil quality.
Dominant plant species
-
western wheatgrass (Pascopyrum smithii), grass
-
slender wheatgrass (Elymus trachycaulus), grass
-
green needlegrass (Nassella viridula), grass
Figure 12. 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 | 1933 | 2448 | 2830 |
Shrub/Vine | 140 | 314 | 560 |
Forb | 140 | 235 | 359 |
Tree | 28 | 141 | 286 |
Total | 2241 | 3138 | 4035 |
Figure 13. Plant community growth curve (percent production by month). NE6634, Eroded Tableland, cool-season dominant.
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 | 15 | 28 | 30 | 10 | 2 | 5 | 5 | 0 | 0 |
Community 1.2
At-Risk Community
The At-Risk or Blue Grama-Western Wheatgrass (Bouteloua gracilis-Pascopyrum smithii) Community (1.2) slowly develops with continuous seasonal grazing, continuous seasonal grazing, or rotational grazing with inadequate growing-season recovery periods. Blue grama and western wheatgrass are the dominant species. Compared to the Reference Community (1.1) green needlegrass and the warm-season tall- and midgrasses have been greatly reduced while buffalograss and sedges have increased and non-native grasses such as Kentucky bluegrass may have begun to invade the plant community. Forb species include white sagebrush, common yarrow, scurfpeas, goldenrod, and hoary verbena. Leadplant has been greatly reduced while western snowberry has increased. American elm, bur oak, green ash, and plains cottonwood are common trees on this site. This plant community is relatively stable but less productive than the Reference Community. Reduction of litter and short plant heights result in higher soil temperatures, poor water infiltration rates, increased runoff, and high evapotranspiration rates. This plant community can occur throughout the site or on spot grazed areas and around water sources where season-long grazing patterns occur. Soil erosion will be minimal due to the sod forming growth form of blue grama. Implementation of key management changes, such as implementing prescribed grazing with appropriate stocking rates and adequate growing season recovery periods, can prevent the crossing of a significant ecological threshold.
Dominant plant species
-
western wheatgrass (Pascopyrum smithii), grass
-
blue grama (Bouteloua gracilis), grass
Figure 14. Annual production by plant type (representative values) or group (midpoint values)
Table 6. Annual production by plant type
Plant type | Low (kg/hectare) |
Representative value (kg/hectare) |
High (kg/hectare) |
---|---|---|---|
Grass/Grasslike | 1154 | 1564 | 1889 |
Forb | 95 | 202 | 347 |
Shrub/Vine | 95 | 202 | 347 |
Tree | – | 50 | 106 |
Total | 1344 | 2018 | 2689 |
Figure 15. Plant community growth curve (percent production by month). NE6636, Eroded Tableland, cool-season/warm-season codominant.
Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
---|---|---|---|---|---|---|---|---|---|---|---|
J | F | M | A | M | J | J | A | S | O | N | D |
5 | 10 | 20 | 25 | 20 | 10 | 5 | 5 |
Pathway 1.1A
Community 1.1 to 1.2
A shift from the Reference Community (1.1) to the At-Risk Community (1.2) occurs with continuous season-long grazing. Rotational grazing with inadequate growing season recovery periods will also cause this shift due to the similar impact to the grazed plants; however, the amount of time needed to cause the shift is often longer. Repetitive haying without allowing adequate recovery periods during the growing season will also facilitate this change.
Pathway 1.2A
Community 1.2 to 1.1
Prescribed grazing with adequate growing season recovery periods will return the At-Risk Community (1.2) to the Reference Community (1.1). Appropriately timed prescribed fire will accelerate this process.
State 2
Native/Invaded Grass State
The Native/Invaded Grass State (2) has been degraded from the Reference State (1) and much of the vegetation present in the Reference State has been replaced by less productive and less palatable plants. Plant species diversity has been significantly reduced both in terms of functional and structural groups and in terms of number of individual species in those groups. Non-native species are typically 15 percent or more of composition in terms the annual production by weight. This plant community developed under repeated seasonal grazing during the summer or under extended periods (more than ten years) of non-use with no fire. Extended periods of non-use cause a thick litter layer to develop. This thatch layer favors cool-season species and invasion of non-native, cool-season grasses, especially Kentucky bluegrass. The loss of tall- and midgrasses has negatively impacted energy flow and nutrient cycling. Water infiltration is reduced due to the shallow root system and rapid runoff characteristics of the invaded plant communities. As the management continues, the plant community will become dominated by non-native cool-season grasses, sedges, and annuals causing the transition to the Invaded Grass State (3). The Native/Invaded Grass State includes the Native/Invasive Grass Community (2.1).
Dominant plant species
-
green ash (Fraxinus pennsylvanica), tree
-
plains cottonwood (Populus deltoides ssp. monilifera), tree
-
western snowberry (Symphoricarpos occidentalis), shrub
-
western wheatgrass (Pascopyrum smithii), grass
-
Kentucky bluegrass (Poa pratensis), grass
-
smooth brome (Bromus inermis), grass
-
Cuman ragweed (Ambrosia psilostachya), other herbaceous
-
white sagebrush (Artemisia ludoviciana), other herbaceous
-
western yarrow (Achillea millefolium var. occidentalis), other herbaceous
Community 2.1
Native/Invasive Grass Community
In the Native-Invasive Grass or Green Needlegrass-Kentucky Bluegrass (Nassella viridula-Poa pratensis) Community (2.1) native, cool-season bunchgrasses have decreased while warm-season tall- and midgrasses have been reduced to remnant populations. This change in the plant composition typically occurs with either continuous, season-long or seasonal grazing in the summer, but also develops with long-term non-use with no fire. Non-native cool-season grasses are a significant proportion of the plant community and are subdominant. Soil health is affected by reduced efficiency in nutrient, mineral, and hydrologic cycles as a result of decreases in rooting depths. Total annual vegetative production has declined significantly. Without a management change, this community will lose most of the native grasses and transition to the Invaded Grass State (3). Initially, the dominant grasses include green needlegrass, blue grama, and Kentucky bluegrass. Other grasses include western wheatgrass, Canada wildrye, and prairie Junegrass. Sedges flourish in the understory. Dominant forbs include Cuman ragweed, scurfpeas, white sagebrush, and verbenas. Shrubs include snowberry and rose. As the management which caused the transition to this state continues, non-native cool-season grasses will increase. Cool, moist climatic conditions tend to increase the proportion of Kentucky bluegrass in the plant community. Compared to the Reference Community (1.1), plant diversity has declined. Soil erosion remains low, but infiltration has decreased and runoff has increased. Once this plant community is reached, a significant amount of time and external resources will be needed to restore ecosystem function.
Dominant plant species
-
bur oak (Quercus macrocarpa), tree
-
green ash (Fraxinus pennsylvanica), tree
-
plains cottonwood (Populus deltoides ssp. monilifera), tree
-
western snowberry (Symphoricarpos occidentalis), shrub
-
Kentucky bluegrass (Poa pratensis), grass
-
green needlegrass (Nassella viridula), grass
-
blue grama (Bouteloua gracilis), grass
Figure 16. Annual production by plant type (representative values) or group (midpoint values)
Table 7. Annual production by plant type
Plant type | Low (kg/hectare) |
Representative value (kg/hectare) |
High (kg/hectare) |
---|---|---|---|
Grass/Grasslike | 801 | 1636 | 2376 |
Shrub/Vine | 196 | 336 | 532 |
Forb | 106 | 168 | 252 |
Tree | 17 | 101 | 202 |
Total | 1120 | 2241 | 3362 |
State 3
Invaded Grass State
The Invaded Grass State (3) occurs when non-native cool-season grasses have invaded and dominate the site. In this state, non-native cool-season grasses are more than 30 percent of the plant community. The loss of native, warm-season, tall- and midgrasses and cool-season bunchgrasses and accompanying increase of nonnative cool-season grasses has negatively impacted energy flow and nutrient cycling. Water infiltration is reduced due to the shallow root system and rapid runoff characteristics of the current plant community. Significant inputs and time are required to move this plant community towards another community and will likely not be possible through grazing management alone due to the loss of plant diversity with the corresponding loss of the seed bank and decreased hydrologic function. Seeding or renovation will likely be needed to improve vegetative production and will move the plant community to the Sodbusted State (6). If management changes are not made following this renovation, the plant community will likely return to the Invaded Grass State. The Invaded Grass State includes the Invaded Grass Community (3.1).
Dominant plant species
-
smooth brome (Bromus inermis), grass
-
Kentucky bluegrass (Poa pratensis), grass
Community 3.1
Invaded Grass Community
The Invaded Grass or Kentucky Bluegrass-Smooth Brome (Poa pratensis-Bromus inermis) Community (3.1) develops with the absence of grazing with no fire or with continued season long grazing or seasonal summer grazing. The plant community is dominated by non-native cool-season grasses, typically Kentucky bluegrass or smooth brome. Western wheatgrass and other native cool-season grasses may be present. Forbs present typically include white sagebrush, goldenrod, scurfpea, and Cuman ragweed. This plant community is resistant to change. Infiltration is moderately reduced while runoff has increased. Soil erosion is low. Plant diversity is significantly reduced. When the plant community is dominated by smooth brome production can be high but smooth brome matures early in the growing season and is palatable for a relatively brief period of time. Production can be increased significantly when the site is managed as pastureland
Dominant plant species
-
Kentucky bluegrass (Poa pratensis), grass
-
smooth brome (Bromus inermis), grass
-
blue grama (Bouteloua gracilis), grass
-
green needlegrass (Nassella viridula), grass
State 4
Early Seral State
The Early Seral State (4) will develop from the Reference State (1), the Native/Invaded Grass State (2), or the Invaded Grass State (3) with severe disturbance and excessive defoliation. This typically arises from heavy concentration of livestock or wildlife. The dominant vegetation includes annual grasses and forbs, and early successional biennial and perennial species. Soil erosion is potentially high. The excessive defoliation causes an extreme reduction in canopy and litter cover, plant density, plant vigor, and root biomass. Soil compaction contributes to decreased water infiltration, increased runoff, and accelerated erosion rates. Significant inputs and time are required to move this plant community towards another community and will not be possible through grazing management alone due to the loss of plant diversity with the corresponding loss of the seed bank, decreased hydrologic function, soil compaction and erosion. Seeding or renovation will be needed to improve vegetative production and will move the plant community to the Sodbusted State (5). If management changes are not made following this renovation, the plant community will likely return to the Invaded Grass State.
Dominant plant species
-
sixweeks fescue (Vulpia octoflora), grass
-
cheatgrass (Bromus tectorum), grass
-
field brome (Bromus arvensis), grass
-
Fendler's threeawn (Aristida purpurea var. fendleriana), grass
-
needle and thread (Hesperostipa comata ssp. comata), grass
-
curlycup gumweed (Grindelia squarrosa), other herbaceous
-
Cuman ragweed (Ambrosia psilostachya), other herbaceous
Community 4.1
Shortgrass/Annuals Community
The Shortgrass/Annuals or Threeawn-Cheatgrass (Aristida-Bromus tectorum) Community (4.1) develops under severe disturbance with heavy continuous season-long grazing and excessive defoliation. This often results from heavy concentration of livestock or wildlife. The dominant vegetation includes pioneer annual grasses and forbs and early successional biennial and perennial species. Grasses may include sixweeks fescue, Fendler threeawn, smooth bromegrass, annual brome, crested wheatgrass, needle and thread, prairie Junegrass and western wheatgrass. Dominant forbs may include curlycup gumweed, lambsquarters, salsify, kochia, field bindweed, thistles, Cuman ragweed, and other early successional species. Shrubs include rose and fringed sagewort. Plant species from adjacent ecological sites may become minor components of this plant community. The community also is susceptible to invasion of other non-native species due to severe soil disturbances and relatively high percent of bare ground. This plant community is resistant to change, as long as soil disturbance or severe vegetation defoliation persists, preventing secondary plant succession. Soil erosion is potentially high. Reduced surface cover, low plant density, low plant vigor, loss of root biomass, and soil compaction, all contribute to decreased water infiltration, increased runoff, and accelerated erosion rates.
State 5
Invaded Woody State
The Invaded Woody State (5) is the result of woody encroachment. Once the tree canopy cover reaches 15 percent with an average tree height exceeding five feet, the threshold to the Invaded Woody State has been crossed. Woody species are increasing due to the lack of prescribed fire, brush management, or other woody tree removal. Typical ecological impacts are a loss of native grasses, reduced diversity of functional and structural groups, reduced forage production, and reduced soil quality. Prescribed burning, wildfire, timber harvest and brush management will move this state toward a grass dominated state. Land that transitioned to the Invaded Woody State from the Native/Invaded Grass State (2), Invaded Grass State (3), Early Seral State (4), or Sodbusted State (6) cannot transition to the Reference State (1) through removal of woody species as the native plant community, soils, and hydrologic function have been too severely impacted for that restoration to occur. The Invaded Woody State includes the Invaded Woody Community (5.1).
Dominant plant species
-
eastern redcedar (Juniperus virginiana), tree
-
needle and thread (Hesperostipa comata ssp. comata), grass
-
Kentucky bluegrass (Poa pratensis), grass
Community 5.1
Invaded Woody Community
The Invaded Woody or Eastern Redcedar (Juniperus virginiana) Community (5.1) has at has at least 15 percent canopy cover consisting of trees generally 5 feet or taller. Encroaching trees are primarily eastern redcedar. Additional woody cover from deciduous trees and shrubs may be present. In the absence of fire and brush management, this ecological site is very susceptible to eastern redcedar seedling invasion, especially when adjacent to a seed source. Eastern redcedar can eventually dominate the site resulting in a closed canopy monoculture which drastically reduces forage production and which has limited value for either livestock grazing or wildlife habitat. With long-term fire suppression, this plant community will develop extensive ladder fuels which can lead to a removal of most tree species with a wildfire. With properly managed intensive grazing, encroachment of deciduous trees will typically be minimal; however, this will not impact encroachment of coniferous species. The herbaceous component decreases proportionately in relation to the percent canopy cover, with the reduction being greater under a coniferous overstory. Eastern redcedar control can usually be accomplished with prescribed burning while the trees are six feet tall or less and fine fuel production is greater than 1,500 pounds per acres. Larger red cedars can also be controlled with prescribed burning, but successful application requires the use of specifically designed ignition and holding techniques (https://www.loesscanyonsburning group.com). Resprouting brush must be chemically treated immediately after mechanical removal to achieve effective treatment. The forb component will initially increase following tree removal. To prevent return to a woody dominated community, ongoing brush management such as hand cutting, chemical spot treatments, or periodic prescribed burning is required. This plant community is resistant to change and resilient given normal disturbances. In higher canopy cover situations, the soil erosion will increase in relation the plant community from which this plant community originated. The hydrologic function is also significantly altered under higher canopy cover. Infiltration is reduced and runoff is typically increased because of a lack of herbaceous cover and the rooting structure provided by the herbaceous species. Total annual production during an average year varies significantly, depending on the production level prior to encroachment and the percentage of canopy cover.
Dominant plant species
-
eastern redcedar (Juniperus virginiana), tree
-
Kentucky bluegrass (Poa pratensis), grass
-
needle and thread (Hesperostipa comata ssp. comata), grass
-
blue grama (Bouteloua gracilis), grass
State 6
Sodbusted State
The threshold to the Sodbusted State (6) is crossed as a result of mechanical disturbance to facilitate production agriculture. If farming operations are suspended, the site can seeded to native grasses and forms resulting in the Reseeded Native Grass Community (6.1), be seeded to a tame pasture forage mixture resulting in the Seeded Pasture Community (6.2) or be abandoned with no seeding which will result in the Natural Reclamation Community (6.3). Permanent alterations of the soil, plant community, and hydrologic cycle make restoration to the Reference State (1) extremely difficult, if not impossible.
Community 6.1
Reseeded Native Grass Community
The Reseeded Native Grass Community (6.1) does not contain native remnants, and varies considerably depending upon the seed mixture, the degree of soil erosion, the age of the stand, fertility management, and past grazing management. Native range and grasslands seeded to native species are ecologically different and should be managed separately. Factors such as functional group, species, stand density, and improved varieties all impact the production level and palatability of the seedings. Species diversity is often limited, and when grazed in conjunction with native rangelands, uneven forage utilization may occur. Total annual production during an average year varies significantly depending upon precipitation, management, and grass species seeded. Prescribed grazing including appropriate utilization levels, adequate growing-season recovery periods, and timing of grazing that favor the productivity, health, and vigor of the seeded species is required to maintain this community. Periodic prescribed burning and brush management may also be needed.
Community 6.2
Seeded Pasture Community
The Seeded Pasture Community (6.2) does not contain native remnants and varies considerably depending upon the extent of soil erosion, the species seeded, the quality of the stand that was established, the age of the stand, and management of the stand since establishment. There are several factors that make seeded tame pasture a different grazing resource than native rangeland and land seeded to a native grass mixture. Factors such as species selected, stand density, improved varieties, and harvest efficiency all impact production levels and palatability. Species diversity on seeded tame pasture is often limited to a few species. When seeded pasture and native rangelands or seeded pasture and seeded rangeland are in the same grazing unit, uneven forage utilization will occur. Improve forage utilization and stand longevity by managing this community separately from native rangelands or land seeded to native grass species. Total annual production during an average year varies significantly depending on the level of management and species seeded. Improved varieties of warm-season or cool-season grasses are recommended for optimum forage production. Fertilization, weed management, and prescribed grazing including appropriate utilization levels, adequate growing-season recovery periods, and timing of grazing that favor the productivity, health, and vigor of the seeded species are required to maintain this community. Periodic prescribed burning and brush management may also be needed.
Community 6.3
Natural Reclamation Community
The Natural Reclamation Community (6.3) consists of annual and perennial weeds and less desirable grasses. These sites have been farmed and abandoned without being reseeded. Soil organic matter and carbon reserves are reduced, soil structure is changed, and a plowpan or compacted layer can form, which decreases water infiltration. Residual synthetic chemicals may remain from farming operations. In early successional stages, this community is not stable. The hazard of erosion is a resource concern. Total annual production during an average year varies significantly depending on the succession stage of the plant community and any management applied to the system.
Transition T1A
State 1 to 2
The Reference State (1) will transition to the Native/Invaded Grass State (2) with the invasion of non-native cool-season grasses caused by long term (more than 10 years) seasonal grazing in summer, continuous season long grazing, or rotational grazing with inadequate growing season recovery periods. This change will also occur with long-term absence of herbivory and fire or annual haying during the same plant growth stage. A significant proportion of the native, cool-season grass species as well as the native, warm-season tall- and midgrasses have been removed from the plant community. Water infiltration and other hydrologic functions are reduced due to the root-matting presence of sod-forming grasses. With the decline and loss of deeper-penetrating root systems, soil structure and biological integrity are degraded. Once this transition occurs, the return to the Reference State may not be feasible.
Transition T2A
State 1 to 4
The Reference State (1) will transition to the Early Seral State (4) with long-term (more than 15 years) severe disturbance with heavy, continuous seasonal or heavy, season long grazing and excessive defoliation. Due to the severe soil disturbance and extreme loss of plant species diversity, return to the Reference State is not feasible.
Transition T1C
State 1 to 5
Disruption of the natural fire regime and the encroachment of invasive exotic and native woody species can cause the Reference State (1) to shift to the Invaded Woody State (5).
Transition T1D
State 1 to 6
The Reference State (1) is significantly altered by tillage to facilitate production agriculture. The disruption to the plant community, soil, and hydrology of the system makes restoration unlikely.
Restoration pathway R2A
State 2 to 1
Long-term (more than 15 years or more) prescribed grazing with adequate growing season recovery periods and appropriate stocking rates timed to coincide with the rapid growth phase of the cool-season grasses will return the Native/Invaded Grass State (2) to the Reference State (1).The length of time required for this restoration depends upon the amount of native grasses remaining in the plant community and will only be feasible if adequate native grasses remain in the plant community. Appropriately timed prescribed burning may accelerate this process.
Transition T2A
State 2 to 3
The Native/Invaded Grass State (2) transitions to the Invaded Grass State (3) when the management that caused the transition to the Native/Invaded Grass State from the Reference State (1) continues. Non-native cool-season grasses continue to increase in abundance, facilitated by seasonal grazing in summer, continuous season long grazing, or rotational grazing with inadequate growing season recovery periods. This transition will also occur with continued non-use with no fire or with continued annual summer haying. Very few, if any, native grasses remain in the plant community resulting in extreme reduction in diversity of functional and structural groups as well as individual species diversity. Water infiltration and other hydrologic functions are reduced due to the root-matting presence of sod-forming grasses. With the decline and loss of deeper-penetrating root systems, soil structure and biotic integrity are degraded. Once this transition occurs, the return to the Native/Invaded State may not be feasible.
Transition T2B
State 2 to 4
The Native/Invaded Grass State (2) will transition to the Early Seral State (4) with long-term (more than 15 years), under severe disturbance with heavy, continuous seasonal or heavy, season long grazing and excessive defoliation. Due to the severe soil disturbance and extreme loss of species diversity return to the Reference State or the Native/Invaded State is not is not feasible.
Transition T2C
State 2 to 5
Disruption of the natural fire regime and the encroachment of invasive exotic and native woody species can cause the Native/Invaded Grass State (2) to shift to the Invaded Woody State (5).
Transition T2D
State 2 to 6
The Native/Invaded Grass State (2) is significantly altered by tillage to facilitate production agriculture. The disruption to the plant community, soil, and hydrology of the system makes restoration unlikely.
Transition T3A
State 3 to 4
The Invaded Grass State (3) will transition to the Early Seral State (4) with long-term (more than 15 years) severe disturbance with heavy, continuous seasonal or heavy, season long grazing and excessive defoliation. Due to the severe soil disturbance and extreme loss of species diversity return to the Reference State is not feasible.
Transition T3B
State 3 to 5
Disruption of the natural fire regime and the encroachment of invasive exotic and native woody species can cause the Invaded Grass State (3) to shift to the Invaded Woody State (5).
Transition T3C
State 3 to 6
The Invaded Grass State (3) is significantly altered by tillage to facilitate production agriculture. The disruption to the plant community, soil, and hydrology of the system makes restoration unlikely.
Transition T4A
State 4 to 5
Disruption of the natural fire regime and the encroachment of invasive exotic and native woody species can cause the Early Seral State (4) to shift to the Invaded Woody State (5).
Transition T4B
State 4 to 6
The Early Seral State (3) is significantly altered by tillage to facilitate production agriculture.
Restoration pathway R5A
State 5 to 1
Prescribed burning, wildfire, harvest, and brush management will move the Invaded Woody State (5) to the Reference State (1). The forb component may initially increase following tree removal. Ongoing brush management such as hand cutting, chemical spot treatments, or periodic prescribed burning is required to prevent a return to the Invaded Woody State. Land that transitioned to the Invaded Woody State from the Native/Invaded Grass State (2), Invaded Grass State (3), Early Seral State (4), or the Sodbusted State 6), cannot be restored to the Reference State (1) through removal of woody species as the native plant community, soils, and hydrologic function have been too severely impacted for that restoration to occur.
Restoration pathway R5B
State 5 to 2
Prescribed burning, wildfire, harvest, and brush management will move the Invaded Woody State (5) to the Native/Invaded Grass State (2). The forb component may initially increase following tree removal. Ongoing brush management such as hand cutting, chemical spot treatments, or periodic prescribed burning is required to prevent a return to the Invaded Woody State. Land that transitioned to the Invaded Woody State from the Native/Invaded Grass State, Invaded Grass State (3), Early Seral State (4), or the Sodbusted State 6), cannot be restored to the Reference State (1) through removal of woody species as the native plant community, soils, and hydrologic function have been too severely impacted for that restoration to occur.
Restoration pathway R5C
State 5 to 3
Prescribed burning, wildfire, harvest, and brush management will move the Invaded Woody State (5) to the Invaded Grass State (3). The forb component may initially increase following tree removal. Ongoing brush management such as hand cutting, chemical spot treatments, or periodic prescribed burning is required to prevent a return to the Invaded Woody State. Land that transitioned to the Invaded Woody State from the Native/Invaded Grass State (2), Invaded Grass State (3), Early Seral State (4), or the Sodbusted State 6), cannot be restored to the Reference State (1) through removal of woody species as the native plant community, soils, and hydrologic function have been too severely impacted for that restoration to occur.
Restoration pathway R5D
State 5 to 4
Prescribed burning, wildfire, harvest, and brush management will move the Invaded Woody State (5) to the Early Seral State (4). The forb component may initially increase following tree removal. Ongoing brush management such as hand cutting, chemical spot treatments, or periodic prescribed burning is required to prevent a return to the Invaded Woody State. Land that transitioned to the Invaded Woody State from the Native/Invaded Grass State (2), Invaded Grass State (3), Early Seral State, or the Sodbusted State 6), cannot be restored to the Reference State (1) through removal of woody species as the native plant community, soils, and hydrologic function have been too severely impacted for that restoration to occur.
Restoration pathway R5E
State 5 to 6
Prescribed burning, wildfire, harvest, and brush management will move the Invaded Woody State (5) to the Sodbusted State (6). The forb component may initially increase following tree removal. Ongoing brush management such as hand cutting, chemical spot treatments, or periodic prescribed burning is required to prevent a return to the Invaded Woody State. Land that transitioned to the Invaded Woody State from the Native/Invaded Grass State (2), Invaded Grass State (3), Early Seral State (4), or the Sodbusted State, cannot be restored to the Reference State (1) through removal of woody species as the native plant community, soils, and hydrologic function have been too severely impacted for that restoration to occur.
Transition T6A
State 6 to 5
Disruption of the natural fire regime and the encroachment of invasive exotic and native woody species can cause the Sodbusted State (6) to shift to the Invaded Woody State (5).
Additional community tables
Table 8. Community 1.1 plant community composition
Group | Common name | Symbol | Scientific name | Annual production (kg/hectare) | Foliar cover (%) | |
---|---|---|---|---|---|---|
Grass/Grasslike
|
||||||
1 | Cool-Season Rhizomatous Grass | 628–1098 | ||||
western wheatgrass | PASM | Pascopyrum smithii | 471–1098 | – | ||
2 | Cool-Season Bunchgrass | 628–785 | ||||
green needlegrass | NAVI4 | Nassella viridula | 314–628 | – | ||
slender wheatgrass | ELTR7 | Elymus trachycaulus | 157–628 | – | ||
Canada wildrye | ELCA4 | Elymus canadensis | 63–314 | – | ||
needle and thread | HECOC8 | Hesperostipa comata ssp. comata | 0–157 | – | ||
porcupinegrass | HESP11 | Hesperostipa spartea | 0–157 | – | ||
prairie Junegrass | KOMA | Koeleria macrantha | 31–94 | – | ||
3 | Warm-Season Tall- and Midgrass | 157–628 | ||||
big bluestem | ANGE | Andropogon gerardii | 63–471 | – | ||
sideoats grama | BOCU | Bouteloua curtipendula | 0–157 | – | ||
prairie sandreed | CALO | Calamovilfa longifolia | 0–157 | – | ||
little bluestem | SCSC | Schizachyrium scoparium | 0–157 | – | ||
Indiangrass | SONU2 | Sorghastrum nutans | 0–157 | – | ||
composite dropseed | SPCOC2 | Sporobolus compositus var. compositus | 0–94 | – | ||
sand dropseed | SPCR | Sporobolus cryptandrus | 0–63 | – | ||
Grass, perennial | 2GP | Grass, perennial | 0–63 | – | ||
4 | Warm-Season Shortgrass | 31–157 | ||||
blue grama | BOGR2 | Bouteloua gracilis | 31–157 | – | ||
buffalograss | BODA2 | Bouteloua dactyloides | 0–94 | – | ||
saltgrass | DISP | Distichlis spicata | 0–63 | – | ||
Grass, perennial | 2GP | Grass, perennial | 0–31 | – | ||
5 | Grass-Like | 31–314 | ||||
sedge | CAREX | Carex | 31–220 | – | ||
Grass-like (not a true grass) | 2GL | Grass-like (not a true grass) | 0–94 | – | ||
Forb
|
||||||
6 | Forb | 157–314 | ||||
Forb, native | 2FN | Forb, native | 31–157 | – | ||
white sagebrush | ARLU | Artemisia ludoviciana | 31–94 | – | ||
American licorice | GLLE3 | Glycyrrhiza lepidota | 31–94 | – | ||
Maximilian sunflower | HEMA2 | Helianthus maximiliani | 31–94 | – | ||
goldenrod | SOLID | Solidago | 31–94 | – | ||
white heath aster | SYER | Symphyotrichum ericoides | 31–94 | – | ||
hoary verbena | VEST | Verbena stricta | 31–63 | – | ||
American vetch | VIAM | Vicia americana | 31–63 | – | ||
wavyleaf thistle | CIUN | Cirsium undulatum | 31–63 | – | ||
prairie clover | DALEA | Dalea | 31–63 | – | ||
mint | MENTH | Mentha | 0–63 | – | ||
scurfpea | PSORA2 | Psoralidium | 31–63 | – | ||
upright prairie coneflower | RACO3 | Ratibida columnifera | 31–63 | – | ||
western yarrow | ACMIO | Achillea millefolium var. occidentalis | 31–63 | – | ||
field sagewort | ARCA12 | Artemisia campestris | 0–63 | – | ||
Cuman ragweed | AMPS | Ambrosia psilostachya | 0–31 | – | ||
false boneset | BREU | Brickellia eupatorioides | 0–31 | – | ||
stiff sunflower | HEPA19 | Helianthus pauciflorus | 0–31 | – | ||
wood lily | LIPH | Lilium philadelphicum | 0–31 | – | ||
dotted blazing star | LIPU | Liatris punctata | 0–31 | – | ||
scarlet beeblossom | GACO5 | Gaura coccinea | 0–31 | – | ||
nettle | URTIC | Urtica | 0–31 | – | ||
Shrub/Vine
|
||||||
7 | Shrub | 157–471 | ||||
western snowberry | SYOC | Symphoricarpos occidentalis | 31–314 | – | ||
American plum | PRAM | Prunus americana | 0–251 | – | ||
Shrub (>.5m) | 2SHRUB | Shrub (>.5m) | 0–251 | – | ||
silver buffaloberry | SHAR | Shepherdia argentea | 0–251 | – | ||
leadplant | AMCA6 | Amorpha canescens | 31–157 | – | ||
chokecherry | PRVI | Prunus virginiana | 0–157 | – | ||
rose | ROSA5 | Rosa | 31–94 | – | ||
false indigo bush | AMFR | Amorpha fruticosa | 0–31 | – | ||
Tree
|
||||||
8 | Tree | 31–251 | ||||
green ash | FRPE | Fraxinus pennsylvanica | 0–251 | – | ||
bur oak | QUMA2 | Quercus macrocarpa | 0–251 | – | ||
American elm | ULAM | Ulmus americana | 0–157 | – | ||
plains cottonwood | PODEM | Populus deltoides ssp. monilifera | 0–157 | – | ||
Tree | 2TREE | Tree | 0–157 | – | ||
boxelder | ACNE2 | Acer negundo | 0–157 | – | ||
common hackberry | CEOC | Celtis occidentalis | 0–157 | – |
Table 9. Community 1.2 plant community composition
Group | Common name | Symbol | Scientific name | Annual production (kg/hectare) | Foliar cover (%) | |
---|---|---|---|---|---|---|
Grass/Grasslike
|
||||||
1 | Cool-Season Rhizomatous Grass | 202–504 | ||||
western wheatgrass | PASM | Pascopyrum smithii | 202–504 | – | ||
2 | Cool-Season Bunchgrass | 101–202 | ||||
green needlegrass | NAVI4 | Nassella viridula | 40–161 | – | ||
Canada wildrye | ELCA4 | Elymus canadensis | 20–101 | – | ||
needle and thread | HECOC8 | Hesperostipa comata ssp. comata | 0–61 | – | ||
slender wheatgrass | ELTR7 | Elymus trachycaulus | 0–40 | – | ||
prairie Junegrass | KOMA | Koeleria macrantha | 20–40 | – | ||
Grass, perennial | 2GP | Grass, perennial | 0–40 | – | ||
3 | Warm-Season Tall- and Midgrass | 40–202 | ||||
sand dropseed | SPCR | Sporobolus cryptandrus | 20–101 | – | ||
composite dropseed | SPCOC2 | Sporobolus compositus var. compositus | 0–61 | – | ||
big bluestem | ANGE | Andropogon gerardii | 0–61 | – | ||
prairie sandreed | CALO | Calamovilfa longifolia | 0–40 | – | ||
sideoats grama | BOCU | Bouteloua curtipendula | 0–40 | – | ||
little bluestem | SCSC | Schizachyrium scoparium | 0–20 | – | ||
4 | Warm-Season Shortgrass | 303–605 | ||||
blue grama | BOGR2 | Bouteloua gracilis | 202–504 | – | ||
buffalograss | BODA2 | Bouteloua dactyloides | 20–202 | – | ||
saltgrass | DISP | Distichlis spicata | 0–101 | – | ||
Grass, perennial | 2GP | Grass, perennial | 0–40 | – | ||
5 | Grass-Like | 40–202 | ||||
sedge | CAREX | Carex | 40–202 | – | ||
Grass-like (not a true grass) | 2GL | Grass-like (not a true grass) | 0–101 | – | ||
6 | Non-Native Cool-Season Grass | 0–202 | ||||
Kentucky bluegrass | POPR | Poa pratensis | 0–161 | – | ||
cheatgrass | BRTE | Bromus tectorum | 0–101 | – | ||
smooth brome | BRIN2 | Bromus inermis | 0–101 | – | ||
Forb
|
||||||
7 | Forb | 101–303 | ||||
white sagebrush | ARLU | Artemisia ludoviciana | 20–101 | – | ||
Forb, native | 2FN | Forb, native | 20–101 | – | ||
Forb, introduced | 2FI | Forb, introduced | 0–101 | – | ||
goldenrod | SOLID | Solidago | 20–81 | – | ||
field sagewort | ARCA12 | Artemisia campestris | 0–61 | – | ||
hoary verbena | VEST | Verbena stricta | 20–61 | – | ||
scurfpea | PSORA2 | Psoralidium | 20–61 | – | ||
western yarrow | ACMIO | Achillea millefolium var. occidentalis | 20–61 | – | ||
wavyleaf thistle | CIUN | Cirsium undulatum | 0–40 | – | ||
Cuman ragweed | AMPS | Ambrosia psilostachya | 20–40 | – | ||
common mullein | VETH | Verbascum thapsus | 0–40 | – | ||
white heath aster | SYER | Symphyotrichum ericoides | 20–40 | – | ||
Canadian horseweed | COCA5 | Conyza canadensis | 0–40 | – | ||
nettle | URTIC | Urtica | 0–40 | – | ||
curlycup gumweed | GRSQ | Grindelia squarrosa | 0–40 | – | ||
dotted blazing star | LIPU | Liatris punctata | 0–20 | – | ||
prairie clover | DALEA | Dalea | 0–20 | – | ||
upright prairie coneflower | RACO3 | Ratibida columnifera | 0–20 | – | ||
Maximilian sunflower | HEMA2 | Helianthus maximiliani | 0–20 | – | ||
American licorice | GLLE3 | Glycyrrhiza lepidota | 0–20 | – | ||
yellow salsify | TRDU | Tragopogon dubius | 0–20 | – | ||
Shrub/Vine
|
||||||
8 | Shrub | 101–303 | ||||
western snowberry | SYOC | Symphoricarpos occidentalis | 40–202 | – | ||
Shrub (>.5m) | 2SHRUB | Shrub (>.5m) | 0–101 | – | ||
rose | ROSA5 | Rosa | 20–61 | – | ||
silver buffaloberry | SHAR | Shepherdia argentea | 0–40 | – | ||
American plum | PRAM | Prunus americana | 0–40 | – | ||
leadplant | AMCA6 | Amorpha canescens | 0–40 | – | ||
chokecherry | PRVI | Prunus virginiana | 0–20 | – | ||
Tree
|
||||||
9 | Tree | 0–101 | ||||
bur oak | QUMA2 | Quercus macrocarpa | 0–101 | – | ||
green ash | FRPE | Fraxinus pennsylvanica | 0–101 | – | ||
common hackberry | CEOC | Celtis occidentalis | 0–61 | – | ||
plains cottonwood | PODEM | Populus deltoides ssp. monilifera | 0–61 | – | ||
Tree | 2TREE | Tree | 0–61 | – | ||
American elm | ULAM | Ulmus americana | 0–61 | – | ||
boxelder | ACNE2 | Acer negundo | 0–61 | – |
Table 10. Community 2.1 plant community composition
Group | Common name | Symbol | Scientific name | Annual production (kg/hectare) | Foliar cover (%) | |
---|---|---|---|---|---|---|
Grass/Grasslike
|
||||||
1 | Cool-Season Rhizomatous Grass | 45–224 | ||||
western wheatgrass | PASM | Pascopyrum smithii | 45–224 | – | ||
2 | Cool-Season Bunchgrass | 22–224 | ||||
green needlegrass | NAVI4 | Nassella viridula | 22–224 | – | ||
prairie Junegrass | KOMA | Koeleria macrantha | 0–90 | – | ||
Canada wildrye | ELCA4 | Elymus canadensis | 0–67 | – | ||
Grass, perennial | 2GP | Grass, perennial | 0–45 | – | ||
slender wheatgrass | ELTR7 | Elymus trachycaulus | 0–22 | – | ||
3 | Warm-Season Tall- and Midgrass | 0–112 | ||||
sand dropseed | SPCR | Sporobolus cryptandrus | 0–112 | – | ||
composite dropseed | SPCO16 | Sporobolus compositus | 0–67 | – | ||
Grass, perennial | 2GP | Grass, perennial | 0–45 | – | ||
4 | Warm-Season Shortgrass | 45–336 | ||||
blue grama | BOGR2 | Bouteloua gracilis | 45–291 | – | ||
saltgrass | DISTI | Distichlis | 0–90 | – | ||
buffalograss | BODA2 | Bouteloua dactyloides | 0–67 | – | ||
Grass, perennial | 2GP | Grass, perennial | 0–45 | – | ||
5 | Grass-like | 22–112 | ||||
sedge | CAREX | Carex | 22–112 | – | ||
Grass-like, perennial | 2GLP | Grass-like, perennial | 0–112 | – | ||
6 | Non-Native Cool-Season Grass | 560–1121 | ||||
Kentucky bluegrass | POPR | Poa pratensis | 224–785 | – | ||
smooth brome | BRIN2 | Bromus inermis | 224–785 | – | ||
cheatgrass | BRTE | Bromus tectorum | 22–224 | – | ||
Forb
|
||||||
7 | Forb | 112–224 | ||||
Forb, introduced | 2FI | Forb, introduced | 0–179 | – | ||
white sagebrush | ARLU | Artemisia ludoviciana | 22–112 | – | ||
common mullein | VETH | Verbascum thapsus | 0–90 | – | ||
field sagewort | ARCA12 | Artemisia campestris | 0–90 | – | ||
Canadian horseweed | COCA5 | Conyza canadensis | 0–90 | – | ||
western yarrow | ACMIO | Achillea millefolium var. occidentalis | 22–90 | – | ||
Forb, native | 2FN | Forb, native | 22–90 | – | ||
hoary verbena | VEST | Verbena stricta | 22–67 | – | ||
goldenrod | SOLID | Solidago | 22–67 | – | ||
yellow salsify | TRDU | Tragopogon dubius | 22–67 | – | ||
white heath aster | SYER | Symphyotrichum ericoides | 22–67 | – | ||
curlycup gumweed | GRSQ | Grindelia squarrosa | 0–67 | – | ||
nettle | URTIC | Urtica | 0–45 | – | ||
Cuman ragweed | AMPS | Ambrosia psilostachya | 22–45 | – | ||
scurfpea | PSORA2 | Psoralidium | 2–45 | – | ||
Shrub/Vine
|
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8 | Shrub | 224–448 | ||||
western snowberry | SYOC | Symphoricarpos occidentalis | 112–448 | – | ||
American plum | PRAM | Prunus americana | 0–112 | – | ||
Shrub (>.5m) | 2SHRUB | Shrub (>.5m) | 0–112 | – | ||
rose | ROSA5 | Rosa | 22–45 | – | ||
silver buffaloberry | SHAR | Shepherdia argentea | 0–22 | – | ||
Tree
|
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9 | Tree | 22–179 | ||||
bur oak | QUMA2 | Quercus macrocarpa | 0–179 | – | ||
green ash | FRPE | Fraxinus pennsylvanica | 0–179 | – | ||
common hackberry | CEOC | Celtis occidentalis | 0–112 | – | ||
American elm | ULAM | Ulmus americana | 0–112 | – | ||
boxelder | ACNE2 | Acer negundo | 0–112 | – | ||
plains cottonwood | PODEM | Populus deltoides ssp. monilifera | 0–112 | – | ||
Tree | 2TREE | Tree | 0–112 | – |
Interpretations
Animal community
LIVESTOCK - GRAZING INTERPRETATIONS:
Grazing by domestic livestock is one of the major income-producing industries in the area. Rangeland in this area may provide year-long forage for cattle, sheep, or horses. During the dormant period, the protein levels of the forage may be lower than the minimum needed to meet livestock (primarily cattle and sheep)requirements. The following table lists suggested stocking rates for cattle under continuous season-long grazing under normal growing conditions. These are conservative estimates that should be used only as guidelines in the initial stages of the conservation planning process. Often, the current plant composition does not entirely match any particular plant community (as described in this ecological site description). Because of this, a field visit is recommended, in all cases, to document plant composition and production. More precise carrying capacity estimates should eventually be calculated using this information along with animal preference data, particularly when grazers other than cattle are involved. With consultation of the land manager, more intensive grazing management may result in improved harvest efficiencies and increased carrying capacity.
Production and Carrying Capacity*
Community 1.1, Reference Community: 2,800 lbs/acre, 0.77 AUM/acre
Community 1.2 At-Risk Community: 1,800 lbs/ac, 0.49 AUM/acre
Community 2.1 Native/Invasive Grass Community: 2,000 lbs/ac, 0.55 AUM/ac
*Based upon the following conditions: continuous season-long grazing by cattle under average growing conditions, 25 percent harvest efficiency. Air dry forage requirements based on 3 percent of animal body weight, or 912 lbs/AU/month.
WILDLIFE INTERPRETATIONS:
Major Land Resource Area (MLRA) 66 lies primarily within the Mixed-grass prairie ecosystem. Though European settlers have converted about a quarter of this landscape to farmland, the majority of the prairie is still intact. This area still consists of diverse grassland habitats interspersed with varying densities of depressional wetlands and limited woody riparian corridors. These habitats historically provided critical life cycle components for the grassland birds, prairie dogs, and herds of roaming bison, elk, and pronghorn. Bobcats, wolves, and mountain lions occupied the apex predator niche. Diverse populations of small mammals and insects still provide a bountiful prey base for raptors and omnivores such as coyotes, foxes, raccoons, and opossums. In addition, a wide variety of reptiles and amphibians thrive in this landscape.
The Mixed-Grass Prairie was a disturbance-driven ecosystem with fire, herbivory, and climate functioning as the primary disturbances. Following European settlement, elimination of fire, overgrazing, and some habitat fragmentation significantly altered the appearance and functionality of the entire ecosystem. Bison and prairie dogs were historically keystone species, but free-roaming bison herds have been extirpated in this region. The loss of bison and fire as ecological drivers greatly influenced the character of the remaining native grasslands and the habitats that they provide. Fragmentation has reduced habitat quality for numerous area-sensitive species, as highlighted by the decline of the greater prairie chicken.
Historically, an ecological mosaic of the sites provided habitat for species requiring unfragmented grasslands. Most of these important habitat features and components are intact, providing upland nesting habitat for grassland birds and game birds; nesting and escape cover for waterfowl; forbs and insects for brood-rearing habitat; and a forage source for small and large herbivores.
Disruption of the natural fire regime and lack of appropriate grazing management are the greatest threats to the ecosystem dynamics today. Tree and shrub encroachment from lack of fire creates habitat that favors generalist species such as American robin and mourning dove, and provides perches for raptors, increasing the predation mortality on native bird populations. Introduced species such as smooth bromegrass, Kentucky bluegrass, nodding plumeless thistle (musk thistle), and Canada thistle further degrade the biological integrity of many areas of the prairie.
Hydrological functions
Water is the principal factor limiting forage production on this site. This site is dominated by soils in hydrologic group B. Infiltration is moderate. Runoff potential for this site varies from negligible to low depending on slope and ground cover. In many cases, areas with greater than 75 percent ground cover have the greatest potential for high infiltration and lower runoff. An example of an exception would be where short grasses form a strong sod and dominate the site. Areas where ground cover is less than 50 percent have the greatest potential to have reduced infiltration and higher runoff (refer to Part 630, NRCS National Engineering Handbook).
Recreational uses
This site provides hunting opportunities for upland game species. The wide variety of plants which bloom from spring until fall have an aesthetic value that appeals to visitors.
Wood products
No appreciable wood products are present on the site.
Other products
Seed harvest of native plant species can provide additional income on this site.
Other information
Field Offices (Counties)
Nebraska:
Ainsworth, (Brown, Keya Paha, and Rock)
Bloomfield, (Knox,)
Spencer, (Boyd)
Neligh, (Antelope)
O'Neill, (Holt)
Valentine, (Cherry)
South Dakota:
Burke, (Gregory)
Martin, (Bennett and Shannon)
Winner, (Tripp)
White River, (Mellette and Todd)
Supporting information
Inventory data references
Information presented here has been derived from NRCS clipping data and other inventory data, and field observations from range trained personnel. Those involved in developing this site include Wayne Bachman, Soil Scientist, NRCS; Stan Boltz, Range Management Specialist, NRCS; Anna Ferguson, Soil Conservationist, NRCS; Roger Hammer, Soil Scientist, NRCS; Dana Larsen, Range Management Specialist, NRCS; Dave Schmidt, Rangeland Management Specialist, NRCS; Kim Stine, Rangeland Management Specialist, NRCS.
Other references
High Plains Regional Climate Center, University of Nebraska.(http://www.hprcc.unl.edu/)
U.S. Department of Agriculture, Natural Resources Conservation Service. 2003. National Range and Pasture Handbook. (https://www.nrcs.usda.gov/national-range-and-pasture-handbook)
U.S. Department of Agriculture, Natural Resources Conservation Service. National Water and Climate Center. (http://www.wcc.nrcs.usda.gov/climate).
U.S. Department of Agriculture, Natural Resources Conservation Service. 2021b. National Soil Information System. (https://www.nrcs.usda.gov/resources/education-and-teaching-materials/national-soil-information-system-nasis).
U.S. Department of Agriculture, Natural Resources Conservation Service. 2021c. National soil survey handbook, title 430-VI. (http://soils.usda.gov/technical/handbook/).
Soil Survey Staff. 2021. Web soil survey. U.S. Department of Agriculture, Natural Resources Conservation Service. (https://websoilsurvey.sc.egov.usda.gov/)
USDA, NRCS. 2001. The PLANTS Database, Version 3.1 (http://plants.usda.gov). National Plant Data Center, Baton Rouge, LA USA.
USDA, NRCS, various published Soil Surveys
Contributors
Stan Boltz
Doug Whisenhunt
Nadine Bishop
Approval
Suzanne Mayne-Kinney, 11/18/2024
Acknowledgments
Many thanks to the members of the soils, local practitioners and technical teams, as well as the editor.
This Ecological Site was approved for publication in March of 2021.
Non-discrimination statement
In accordance with Federal civil rights law and U.S. Department of Agriculture (USDA) civil rights regulations and policies, the USDA, its Agencies, offices, and employees, and institutions participating in or administering USDA programs are prohibited from discriminating based on race, color, national origin, religion, sex, gender identity (including gender expression), sexual orientation, disability, age, marital status, family/parental status, income derived from a public assistance program, political beliefs, or reprisal or retaliation for prior civil rights activity, in any program or activity conducted or funded by USDA (not all bases apply to all programs). Remedies and complaint filing deadlines vary by program or incident.
Persons with disabilities who require alternative means of communication for program information (e.g., Braille, large print, audiotape, American Sign Language, etc.) should contact the responsible Agency or USDA's TARGET Center at (202) 720-2600 (voice and TTY) or contact USDA through the Federal Relay Service at (800) 877-8339. Additionally, program information may be made available in languages other than English.
To file a program discrimination complaint, complete the USDA Program Discrimination Complaint Form, AD-3027, found online at How to File a Program Discrimination Complaint and at any USDA office or write a letter addressed to USDA and provide in the letter all of the information requested in the form. To request a copy of the complaint form, call (866) 632-9992. Submit your completed form or letter to USDA by: (1) mail: U.S. Department of Agriculture, Office of the Assistant Secretary for Civil Rights, 1400 Independence Avenue, SW, Washington, D.C. 20250-9410; (2) fax: (202) 690-7442; or (3) email:
program.intake@usda.gov.
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) | Original Author: Stan Boltz Version V participants: Emily Helms, Nadine Bishop, Jeff Nichols |
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Contact for lead author | Jeff Nichols Nebraska State Range Conservationist jeffrey.nichols@usda.gov |
Date | 11/18/2024 |
Approved by | Suzanne Mayne-Kinney |
Approval date | |
Composition (Indicators 10 and 12) based on | Annual Production |
Indicators
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Number and extent of rills:
None. Rills are not expected on this site. -
Presence of water flow patterns:
None. Water flow patterns are not expected on this site. -
Number and height of erosional pedestals or terracettes:
None. Pedestals and terracettes should not be present on this site. -
Bare ground from Ecological Site Description or other studies (rock, litter, lichen, moss, plant canopy are not bare ground):
Bare ground is typically 5 percent or less.
Bare ground is exposed mineral soil that is not covered by vegetation (basal and/or foliar canopy), standing dead vegetation, gravel/rock, and visible biological crust (e.g. lichen, mosses, algae). -
Number of gullies and erosion associated with gullies:
None. Gullies are not expected on this site. -
Extent of wind scoured, blowouts and/or depositional areas:
None. Wind-scoured areas and depositional areas are not expected on this site. -
Amount of litter movement (describe size and distance expected to travel):
None. Litter should fall in place and litter movement should not occur on the site. -
Soil surface (top few mm) resistance to erosion (stability values are averages - most sites will show a range of values):
Soil stability ratings should typically be 5 to 6, normally 6. Surface organic matter adheres to the soil surface. Soil surface fragments will typically retain structure indefinitely when dipped in distilled water. -
Soil surface structure and SOM content (include type of structure and A-horizon color and thickness):
The A-horizon should be 7 to 24 inches (18-60 cm) thick (Bigbend is 3 inches). Soil is very dark gray, dark grayish brown, or gray (values of 4 to 5) when dry and dark brown, very dark grayish brown, or very dark brown (values of 2 or 3) when moist; Bigbend, Nimbro, and Haynie may be dark grayish brown or grayish brown (value of 5),. Structure is variable with soil series and ranges from granular to subangular blocky to platy.
The primary soils correlated to the Loamy Terrace ecological site include Shell, Bigbend, Grigston, Bridgeport, Brocksburg, Hall, Haynie, and Nimbro. Other soils correlated to the site include Bonn, Hillmoe, Blake and Cass. -
Effect of community phase composition (relative proportion of different functional groups) and spatial distribution on infiltration and runoff:
The functional/structural groups provide a combination of rooting depths and structure which positively influences infiltration. Combination of shallow and deep rooted species (mid & tall rhizomatous and tufted perennial cool-season grasses) with fine and coarse roots positively influences infiltration. Large amounts of Kentucky bluegrass or encroachment of eastern redcedar may have an adverse impact on infiltration and runoff.
The expected composition of the plant community is 75 to 85 percent perennial grasses and grass-likes, 5 to 10 percent forbs, 5 to 10 percent shrubs, and trees (1-5%). The perennial grass and grass-like component is made up of C3 rhizomatous grasses (20-35%), C3 bunchgrasses (20-25%), C4 tall- and midgrasses (5-20%), grass-likes (1-10%), and C4 shortgrasses (1-5%). -
Presence and thickness of compaction layer (usually none; describe soil profile features which may be mistaken for compaction on this site):
None. A compaction layer should not be present. -
Functional/Structural Groups (list in order of descending dominance by above-ground annual-production or live foliar cover using symbols: >>, >, = to indicate much greater than, greater than, and equal to):
Dominant:
Phase 1.1
1. Native, perennial, C3 rhizomatous grass, 560-980 #/ac, 20-35% (1 species minimum): western wheatgrass.
2. Native, perennial, C3 bunchgrass, 560-700 #/ac, 20-25% (4 species minimum): green needlegrass, slender wheatgrass, Canada wildrye, needle and thread, porcupinegrass, prairie Junegrass.
Phase 1.2
1. Native, perennial, C4 shortgrass, 270-540 #/ac, 15-30% (2 species minimum): blue grama, buffalograss, saltgrass.
2. Native, perennial, C3 rhizomatous grass, 180-450 #/ac, 10-25% (1 species minimum): western wheatgrass.
Phase 1.3
1. Native, perennial, C3 bunchgrass (2 species minimum): green needlegrass, Canada wildrye, needle and thread, slender wheatgrass, prairie Junegrass.
2. Native, perennial, C4 shortgrass (2 species minimum): blue grama, buffalograss, saltgrass.Sub-dominant:
Phase 1.1
1. Native, perennial, C4 tall- and midgrass, 140-560 #/ac, 5-20% (1 species minimum): big bluestem, sideoats grama, prairie sandreed, little bluestem, Indiangrass, composite dropseed.
2. Forb, 140-420 #/ac, 10-15% (10 species minimum): white sagebrush, American licorice, Maximilian sunflower, goldenrod, white heath aster, American vetch, purple prairie clover, upright prairie coneflower, western yarrow and other forbs that vary from location to location.
Phase 1.2
1. Forb, 90-270 #/ac, 5-15% (6 species minimum): white sagebrush, goldenrod, hoary verbena, western yarrow, Cuman ragweed, white heath aster and other forbs that vary from location to location.
2. Shrub, 90-270 #/ac, 5-15% (2 species minimum): western snowberry, rose and other shrubs that vary from location to location.
Phase 1.3
1. Grass-like (1 species minimum): sedges.
2. Native, perennial, C3, rhizomatous grass (1 species minimum): western wheatgrass.Other:
Minor - Phase 1.1
1. Shrub, 140-280 #/ac, 5-10%: western snowberry, leadplant, rose, and other shrubs that vary from location to location.
2. Grass-likes, 28-280 #/ac, 1-10%: sedges.
3. Native, perennial, C4, shortgrass, 40-280 #/ac, 1-5%: blue grama, buffalograss, saltgrass.
4. Native trees, 28-140 #/ac, 1-5%: green ash, bur oak and other trees which vary from location to location.
Minor - Phase 1.2
1. Native, perennial, C3 bunchgrass, 90-180 #/ac, 5-10%: green needlegrass, Canada wildrye, needle and thread, slender wheatgrass, prairie Junegrass.
2. Grass-like, 36-180 #/ac, 2-10%: sedges.
3. Non-native, C3 grass, 0-180 #/ac, 0-10%: Kentucky bluegrass, cheatgrass, smooth brome.
4. Native, perennial, C4, tall- and midgrass, 26-180 #/ac, 2-5 %: big bluestem, composite dropseed, little bluestem, prairie sandreed, sand dropseed, sideoats grama.
5. Native trees, 0-90 #/ac, 0-5%: green ash, bur oak and other trees that vary from location to location.
Minor - Phase 1.3
1. Non-native, C3 grass: Kentucky bluegrass, cheatgrass, smooth brome.
2. Native, perennial, C4, tall- and midgrass: big bluestem, composite dropseed, little bluestem, prairie sandreed, sand dropseed, sideoats grama.
3. Shrub: shrubs present vary from location to location.
4. Native forbs: forbs present vary from location to location.
5. Native tree: trees present vary from location to location.Additional:
-
Amount of plant mortality and decadence (include which functional groups are expected to show mortality or decadence):
Bunch grasses have strong, healthy centers with few (less than 3 percent) dead centers. Shrubs may show some dead branches (less than 5 percent) as plants age. -
Average percent litter cover (%) and depth ( in):
Plant litter cover is evenly distributed throughout the site and is expected to be 80 to 90 percent and at a depth of 0.50 to 1.0 inch (1.3 to 2.6 cm). Excessive Kentucky bluegrass litter may impact the functionality of the site -
Expected annual annual-production (this is TOTAL above-ground annual-production, not just forage annual-production):
The representative value (RV) for annual production is 2,800 pounds per acre on an air dry weight basis. Low and High production years should yield 2,000 and 3,600 pounds per acre respectively.. -
Potential invasive (including noxious) species (native and non-native). List species which BOTH characterize degraded states and have the potential to become a dominant or co-dominant species on the ecological site if their future establishment and growth is not actively controlled by management interventions. Species that become dominant for only one to several years (e.g., short-term response to drought or wildfire) are not invasive plants. Note that unlike other indicators, we are describing what is NOT expected in the reference state for the ecological site:
No non-native invasive species are present. Annual bromes (cheatgrass and Japanese/field), leafy spurge, Canada thistle, smooth brome, Kentucky bluegrass, Russian olive, and eastern redcedar are known invasives that have the potential to become dominant or co-dominant on this site. Consult the state noxious weed and state watch lists for potential invasive species.
Note: species that become dominant for only one to several years (e.g., short-term response to drought or wildfire) are not invasive plants. -
Perennial plant reproductive capability:
All perennial species exhibit high vigor relative to recent weather conditions. Perennial grasses should have vigorous rhizomes or tillers; vegetative and reproductive structures are not stunted. All perennial species should be capable of reproducing annually.
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The Ecosystem Dynamics Interpretive Tool is an information system framework developed by the USDA-ARS Jornada Experimental Range, USDA Natural Resources Conservation Service, and New Mexico State University.
Click on box and path labels to scroll to the respective text.
Ecosystem states
States 1, 5 and 6 (additional transitions)
States 2, 5 and 6 (additional transitions)
T1A | - | Invasion of non-native cool-season grasses, long term (>10 years) seasonal grazing in summer, continuous season long grazing, rotational grazing with inadequate growing season recovery periods or non-use with no fire. |
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T2A | - | Long term (> 15 years) severe disturbance or heavy, concentrated, continuous season long grazing or seasonal grazing. |
T1C | - | Woody encroachment with no prescribed burning or woody species management. |
T1D | - | Tillage to facilitate production agriculture. |
R2A | - | Long-term (> 15 years) prescribed grazing during spring or spring and fall. |
T2A | - | Continued invasion of non-native cool-season grasses facilitated by seasonal grazing in summer, continuous season long grazing, rotational grazing with inadequate growing season recovery periods or non-use with no fire. |
T2B | - | Long term (> 15 years) severe disturbance or heavy, concentrated, continuous season long grazing or seasonal grazing. |
T2C | - | Woody encroachment with no prescribed burning or woody species management. |
T2D | - | Tillage to facilitate production agriculture. |
T3A | - | Long term (> 15 years) severe disturbance or heavy, concentrated, continuous season long grazing or seasonal grazing. |
T3B | - | Woody encroachment with no prescribed burning or woody species management. |
T3C | - | Tillage to facilitate production agriculture. |
T4A | - | Woody encroachment with no prescribed burning or woody species management. |
T4B | - | Tillage to facilitate production agriculture. |
R5A | - | Prescribed burning, wildfire, timber harvest, brush management. |
R5B | - | Prescribed burning, wildfire, timber harvest, brush management. |
R5C | - | Prescribed burning, wildfire, timber harvest, brush management. |
R5D | - | Prescribed burning, wildfire, timber harvest, brush management. |
R5E | - | Prescribed burning, wildfire, timber harvest, brush management. |
T6A | - | Woody encroachment with no prescribed burning or woody species management. |
State 1 submodel, plant communities
1.1A | - | Continuous season-long grazing or repetitive haying. |
---|---|---|
1.2A | - | Prescribed grazing with adequate growing season recovery periods. |