Natural Resources
Conservation Service
Ecological site R102CY048NE
Loamy Overflow
Last updated: 6/28/2024
Accessed: 11/13/2024
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.
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.
Classification relationships
"Silty Overflow" range sites for NE NRCS Vegetation Zones 3 & 4
NE Natural Heritage Program/NE Game & Parks Commission: "Lowland Tallgrass Prairie"
General information for MLRA 102C:
*Fenneman (1916) Physiographic Regions*
Division - Interior Plains
East:
Province - Central Lowland
Section - Till Plains
West:
Province - Great Plains
Section - High Plains
*USFS (2007) Ecoregions*
Domain - Humid Temperate
Division - Prairie
Province - Prairie Parkland (Temperate)
Section - North-Central Glaciated Plains (251B)
*EPA Ecoregions (Omernik 1997)*
I - Great Plains (9)
II - Temperate Prairies (9.2)
III - Western Corn Belt Plains (9.2.3) IV - Loess Prairies (47a)
IV - Northeastern Nebraska Loess Hills (47k)
IV - Transitional Sandy Plain (47l)
Ecological site concept
This site is found on active floodplains subject to inundation but lacking a water table within 102 centimeters (40 inches). Additional moisture is received as run-on originating from higher on the landscape, but occasional to frequent flooding also acts to suppress production at times and redistribute soil and plant materials through erosion and deposition.
Associated sites
R102CY046NE |
Subirrigated May be intermixed, and generally found local elevation is relatively low. |
---|---|
R102CY050NE |
Loamy Lowland Generally found on higher terrace positions which formed under flooding, but no longer function as an active floodplain. |
Similar sites
R102CY050NE |
Loamy Lowland These sites will have mollic soils without stratification, typically starting at the first tread above the active floodplain. They also will not exhibit signs of flooding such as drift deposits or water marks. |
---|
Table 1. Dominant plant species
Tree |
Not specified |
---|---|
Shrub |
Not specified |
Herbaceous |
(1) Andropogon gerardii |
Physiographic features
This site predominantly occurs on nearly level to gently sloping floodplains of river valleys, and in drainageways and draws of uplands (0-5% slopes) and are susceptible to occasional or frequent overflow that occurs from flooding of streams or run-in from a higher slope above. It predominantly receives runoff from adjacent sites, some have a seasonally high water table from 94 to 168 centimeters (37 to 66 inches) from October-July, while in others the water table is greater than 203 centimeters (80 inches), it does not pond, and at least occasionally floods for a brief duration.
Table 2. Representative physiographic features
Landforms |
(1)
Flood plain
(2) Alluvial fan (3) Drainageway |
---|---|
Runoff class | Negligible to medium |
Flooding duration | Very brief (4 to 48 hours) to brief (2 to 7 days) |
Flooding frequency | Occasional to frequent |
Elevation | 1,100 – 1,840 ft |
Slope | 5% |
Water table depth | 37 – 80 in |
Aspect | Aspect is not a significant factor |
Climatic features
Most of the rainfall occurs as high-intensity, convective thunderstorms during the growing season. Peak precipitation occurs from the middle of spring to early in autumn. Winter precipitation occurs as snow (USDA/NRCS 2006).
The average annual temperature gradient trends higher from north (45°F/7°C) to south (51°F/11°C).
The average annual precipitation gradient trends higher from northwest (64 centimeters / 25 inches) to southeast (79 centimeters / 31 inches).
The annual snowfall ranges from about 60 centimeters (24 inches) in the southern part of the area to 85 centimeters (34 inches) in the northern part.
The following data summary includes weather stations representing the full geographic extent of the MLRA, and is based on 70% probabilities (NOAA/UNL) meaning that actual observed climate conditions may fall outside these ranges 30% of the time. Furthermore, climatic events can manifest many different ways. For example, abnormally dry periods could occur as 3 consecutive drought years out of 10, 3 individual years separated by “normal” years, or some combination. Tree-ring records indicate that portions of the Great Plains have also historically experienced droughts lasting several decades, so plant community response will largely depend on the manner in which climatic variability is realized in interaction with past and current land management.
Table 3. Representative climatic features
Frost-free period (characteristic range) | 124-142 days |
---|---|
Freeze-free period (characteristic range) | 143-172 days |
Precipitation total (characteristic range) | 28-29 in |
Frost-free period (actual range) | 122-149 days |
Freeze-free period (actual range) | 141-178 days |
Precipitation total (actual range) | 28-32 in |
Frost-free period (average) | 133 days |
Freeze-free period (average) | 158 days |
Precipitation total (average) | 29 in |
Figure 2. Monthly precipitation range
Figure 3. Monthly minimum temperature range
Figure 4. Monthly maximum temperature range
Figure 5. Monthly average minimum and maximum temperature
Figure 6. Annual precipitation pattern
Figure 7. Annual average temperature pattern
Climate stations used
-
(1) COLUMBUS 3 NE [USC00251825], Columbus, NE
-
(2) OAKDALE [USC00256135], Oakdale, NE
-
(3) CROFTON [USC00252037], Crofton, NE
-
(4) HAWARDEN [USC00133718], Hawarden, IA
-
(5) SIOUX FALLS 14 NNE [USW00004990], Garretson, SD
-
(6) VALLEY NWS [USC00258795], Valley, NE
Influencing water features
This site occurs on nearly level areas that receive additional water from overflow of intermittent or perennial streams, or runoff from adjacent slopes. The site floods occasionally to frequently.
Soil features
These are predominantly very deep, moderately well to well drained soils. The surface texture is predominantly silt loam, silty clay loam, or loam from 0 to 25 centimeters (0 to 10 inches) and the Subsurface Texture Group is Loamy from 25 to 203 centimeters (10 to 80 inches).
Rills and gullies are not inherent to this site. Water flow patterns, if present, should be irregular and disconnected, and pedestalling none to slight; although, both of these indicators may become more apparent as slope approaches the upper limit for the site. Soil aggregate stability should be high.
Major soils assigned to this site include Aowa, Blyburg, Bon, Hobbs, Janude, Kennebec, McPaul, Nodaway, Roxbury, Shell.
Table 4. Representative soil features
Parent material |
(1)
Alluvium
|
---|---|
Surface texture |
(1) Silty clay loam (2) Silt loam (3) Loam |
Family particle size |
(1) Loamy |
Drainage class | Moderately well drained to well drained |
Permeability class | Moderately slow to rapid |
Soil depth | 80 in |
Surface fragment cover <=3" | 3% |
Surface fragment cover >3" | Not specified |
Available water capacity (0-40in) |
7 – 9.4 in |
Calcium carbonate equivalent (0-40in) |
5% |
Electrical conductivity (0-40in) |
2 mmhos/cm |
Sodium adsorption ratio (0-40in) |
Not specified |
Soil reaction (1:1 water) (0-40in) |
5.6 – 8.4 |
Subsurface fragment volume <=3" (Depth not specified) |
3% |
Subsurface fragment volume >3" (Depth not specified) |
Not specified |
Ecological dynamics
This site is found on active floodplains subject to inundation, but lacking a water table within
102 centimeters (40 inches). Additional moisture is received as run-on originating from higher on the landscape, but occasional to frequent flooding also acts to suppress production at times and redistribute soil and plant materials through erosion and deposition.
This site developed with fire as an integral part of the ecological processes and grassland maintenance. It is presumed that the historic fires generally occurred every 3-4 years, were randomly distributed, and ignited by lightning at various times throughout the summer when thunderstorms were likely to occur. Furthermore, it is also believed that pre-European inhabitants often used fire as a management tool for attracting herds of large migratory herbivores (bison, elk, and/or deer) as well as for warfare. However, the impact of fire over the past 100 years has been diminished due to human prevention and suppression of wildfire and the pervasive lack of cultural acceptance of prescribed fire as a surrogate (Helzer 2010).
The degree of herbivory (feeding on herbaceous plants) has a significant impact on the dynamics of the site. Historically, periodic grazing by herds of large migratory herbivores was a primary influence; however, herbivory by species such as insects, rodents, and root feeding organisms also impacted the vegetation historically and continue to this day (Helzer 2010). Human control of large herbivore impacts through grazing of domestic livestock and/or manipulation of wildlife populations has been a major contemporary influence on the ecological dynamics of the site (USDA/SCS 1977) and this management coupled with climate largely dictates the plant communities observed.
The reference state characterizes the historic natural condition and has been determined by the study of rangeland relic areas, areas protected from excessive disturbance, and/or areas under compatible grazing regimes. Trends in plant community dynamics ranging from heavily grazed to unused areas, seasonal use pastures, and historical accounts have also been considered.
The following is a diagram illustrating predictable and recurring plant communities inherent to this site, and the pathways of change between them (Bestelmeyer 2010). The ecological processes will be discussed in more detail in the plant community descriptions following the diagram.
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
States 1, 5 and 2 (additional transitions)
T1A | - | Non-native grasses increase |
---|---|---|
T1B | - | Disturbance; annual species dominant |
T1C | - | Woody species dominate |
R2A | - | Restoration inputs; native warm season grasses dominate |
T2A | - | Increasing dominance of cool season grasses |
T2B | - | Disturbance; annual species dominant |
T2C | - | Woody species dominate |
T3A | - | Management inputs; increase of warm season grasses |
T3B | - | Cool season grasses dominate the site |
T3A | - | Woody species continue to increase and dominant the site |
R4A | - | Restoration inputs; warm season grasses dominant |
R5A | - | Restoration inputs to promote warm season grasses |
State 1 submodel, plant communities
1.1A | - | Intense grazing with inadequate recover periods |
---|---|---|
1.2A | - | Grazing management with adequate recovery periods |
State 2 submodel, plant communities
2.1A | - | Increasing dominance of non-native grasses |
---|---|---|
2.2A | - | Management to promote warm-season grasses |
State 3 submodel, plant communities
State 4 submodel, plant communities
State 5 submodel, plant communities
State 1
Native tallgrass
This state comprises the communities within the range of natural variability under historic conditions and disturbance regimes. Patterns created by wildlife use and fire would have created a mosaic of communities across the landscape; however, warm-season tallgrasses are dominant, with a subdominant to minor contribution from native cool-season grasses, forbs, and shrubs. Fire and bison herbivory were the dominant disturbance regimes that historically maintained the tallgrass dominance with a diverse forb component. Furthermore, bison grazing was closely linked to fire patterns as the animals preferred grazing burned areas offering lush regrowth devoid of decadence and of higher nutritive quality. Thus, historic plant communities were subjected to occasional burning and grazing, with substantial rest/recovery periods as the fuel load rebuilt to eventually start this process again. Fire return intervals of 3-4 years served to suppress woody species, particularly the various deciduous tree and shrub species prevalent in adjacent riparian corridors. The degree to which observed conditions represent this state largely depends on how closely the management has mimicked these past disturbance effects.
Dominant plant species
-
big bluestem (Andropogon gerardii), grass
-
little bluestem (Schizachyrium scoparium), grass
Community 1.1
Big bluestem-Little bluestem (Andropogon gerardii-Schizachyrium scoparium)
This is the interpretive plant community and can be found on areas that are properly managed with prescribed grazing that allows for adequate recovery periods following each grazing event. The plant community consists of 85-95% grasses and grass-likes, 5-10% forbs and 0-5% shrubs. Dominant grasses include big bluestem, little bluestem, indiangrass, and switchgrass. Other grasses and grass-likes are sideoats grama, western wheatgrass, and sedges. Forb species are diverse and often include western ragweed and Missouri goldenrod. Common shrubs include western snowberry and eastern poison ivy. This plant community is diverse, stable, and productive. Plant community dynamics, nutrient cycles, water cycles, and energy flow are functioning properly. Plant litter is properly distributed with negligible movement off-site and natural plant mortality is very low. This community is resistant to many disturbances except continuous, season-long heavy grazing, tillage, or non-use. Broadcast herbicide application will dramatically reduce forb diversity and abundance. Total annual production, during an average year, ranges from 2,650 to 3,750 pounds per acre air-dry weight and will average 3,200 pounds.
Dominant plant species
-
big bluestem (Andropogon gerardii), grass
-
little bluestem (Schizachyrium scoparium), grass
Figure 9. Annual production by plant type (representative values) or group (midpoint values)
Table 5. Annual production by plant type
Plant type | Low (lb/acre) |
Representative value (lb/acre) |
High (lb/acre) |
---|---|---|---|
Grass/Grasslike | 2511 | 2880 | 3194 |
Forb | 145 | 240 | 370 |
Shrub/Vine | 0 | 80 | 180 |
Total | 2656 | 3200 | 3744 |
Figure 10. Plant community growth curve (percent production by month). NE1021, 102C Warm-season. Warm-season grass, MLRA 102C.
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 | 2 | 7 | 18 | 23 | 26 | 16 | 6 | 2 | 0 | 0 |
Community 1.2
Little bluestem-Sideoats grama (Schizachyrium scoparium-Bouteloua curtipendula)
Midgrasses, typically sideoats grama and little bluestem, dominate the site with tallgrass remnants scattered throughout. While still within the range of natural variability, energy capture, nutrient cycling, and hydrology are not functioning at their full potential relative to the reference condition.
Dominant plant species
-
sideoats grama (Bouteloua curtipendula), grass
-
little bluestem (Schizachyrium scoparium), grass
Figure 11. Plant community growth curve (percent production by month). NE1021, 102C Warm-season. Warm-season grass, MLRA 102C.
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 | 2 | 7 | 18 | 23 | 26 | 16 | 6 | 2 | 0 | 0 |
Pathway 1.1A
Community 1.1 to 1.2
Grazing management which does not provide adequate recovery periods for tallgrass species will shift towards shorter statured species, particularly little bluestem and sideoats grama. Likewise, shortgrasses such as blue grama will also increase. Periods of extended drought will have similar impacts and cause a shift towards mixed-grass/shortgrass prairie species that are better adapted to drier conditions.
Pathway 1.2A
Community 1.2 to 1.1
Grazing management that includes proper stocking rates with adequate recovery periods for the entire grazing unit is usually required to improve or maintain this site. Intensive grazing management using concentrated livestock numbers, combined with long recovery periods, can be beneficial in improving forage utilization, quantity, and quality. Favorable precipitation following drought will promote tallgrass species and facilitate a return to the reference community.
State 2
Native/invaded mix
This state can manifest three ways: 1) the appearance of introduced cool-season grasses, 2) the expansion of deciduous shrubs and/or trees, or 3) some combination of these. Kentucky bluegrass and smooth brome are the primary cool-season grass invaders in this region, commonly found in roadsides, disturbed areas, and pastures intentionally seeded for cool-season forage. Management practices and/or environmental conditions that are not favorable to native grass vigor may allow introduced grasses to invade the site thereby decreasing native diversity and abundance, particularly of forbs. In the absence of the historic fire regime, woody deciduous species may also expand to become an influential component of the community. The invasive component tends to have very high reslience, is extremely difficult to eradicate, and what might be considered a new "contemporary" range of natural variability is seen as competition between the native grasses and introduced/woody species for space and resources.
Dominant plant species
-
little bluestem (Schizachyrium scoparium), grass
-
sideoats grama (Bouteloua curtipendula), grass
-
smooth brome (Bromus inermis), grass
-
Kentucky bluegrass (Poa pratensis), grass
Community 2.1
Subdominant Smooth brome-Kentucky bluegrass (Bromus inermis-Poa pratensis)
While native grasses still dominate the site, introduced cool-season species have established a foothold in the system and can be found interspersed throughout the stand. The stand may still have a native tallgrass appearance overall, but bluegrass and/or brome can be easily found. Deciduous shrub/tree species may also have begun to expand into areas where they did not persist historically, but the overall appearance can vary depending on the propagation method of a particular species. Seed propagated species, such as Siberian elm, tend to colonize further from the parent plant and affect larger areas, but in lower densities. In contrast, rhizomatous species such as smooth sumac tend to progress as a higher-density encroachment spreading directly from the parent plants.
Dominant plant species
-
little bluestem (Schizachyrium scoparium), grass
-
sideoats grama (Bouteloua curtipendula), grass
-
smooth brome (Bromus inermis), grass
-
Kentucky bluegrass (Poa pratensis), grass
Figure 12. Plant community growth curve (percent production by month). NE1022, Warm-season dominant, cool-season subdominant.
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 | 2 | 9 | 19 | 23 | 24 | 13 | 7 | 3 | 0 | 0 |
Community 2.2
Codominant Smooth brome-Kentucky bluegrass (Bromus inermis-Poa pratensis)
This community is comprised of a relatively even mix of native grasses and invasive species overall. This may manifest as a well-distributed interspersion of natives and invaders, as distinct patches wherein the competitors dominate locally, or some combination. Forb diversity and abundance is further diminished.
Dominant plant species
-
smooth brome (Bromus inermis), grass
-
little bluestem (Schizachyrium scoparium), grass
-
Kentucky bluegrass (Poa pratensis), grass
-
sideoats grama (Bouteloua curtipendula), grass
Figure 13. Plant community growth curve (percent production by month). NE1023, Warm-season, cool-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 |
0 | 0 | 3 | 10 | 23 | 26 | 16 | 10 | 7 | 4 | 1 | 0 |
Pathway 2.1A
Community 2.1 to 2.2
Management and/or environmental conditions have afforded a persisting competitive advantage to introduced cool-season grasses, and they begin to dominate the ecological dynamics of the site. The robust invasive component is able to quickly and effectively exploit opportunities to outcompete and displace natives. Repeated summer use of an area will place the bulk of stressor impacts on native plants, reducing native vigor and allowing invaders to thrive. Likewise, a climate pattern limiting natural moisture to the spring and fall months coincides with peak cool-season growth and may support a similar process.
Pathway 2.2A
Community 2.2 to 2.1
The native component remains in an abundance that can facilitate a return towards more historic conditions if management is modified to shift stressor impacts to the invasive species, and promote warm-season grass vigor. Environmental conditions and/or disturbance regimes that strongly favor warm-season grasses can also trend the site towards the reference.
State 3
Invasive dominant
Cool-season invasion has progressed to the point that native species comprise a negligible portion of the community and the aggressively rhizomatous invasives preclude warm-season tallgrass germination and seedling survival. The native component may be completely absent, and the site resembles a seeded pasture. Woody competitiveness for sunlight, water, space, and other resources continues to increase as desirable herbaceous species are shaded out, crowded out, or otherwise suppressed.
Dominant plant species
-
smooth brome (Bromus inermis), grass
-
Kentucky bluegrass (Poa pratensis), grass
Community 3.1
Smooth brome-Kentucky bluegrass (Bromus inermis-Poa pratensis)
This community is typically composed of smooth brome with bluegrass interspersed among the brome tillers. Warm-season natives, if present, are sparse yet often conspicuous due to pronounced differences in growth habits and metabolic pathways. Community structure and function have been dramatically simplified relative to the reference condition, and very few biotic functional groups are represented in amounts that would influence ecological function. The invasive grass root skein provides good site stability; however, replacement of the deeper roots and complex bunchgrass canopy with the shallower roots and erect tiller canopy of the invaders results in reduced interception and infiltration rates.
Dominant plant species
-
smooth brome (Bromus inermis), grass
-
Kentucky bluegrass (Poa pratensis), grass
Figure 15. Plant community growth curve (percent production by month). NE1024, Cool-season. Smooth brome/Kentucky bluegrass.
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 | 4 | 13 | 25 | 28 | 8 | 6 | 9 | 5 | 2 | 0 |
State 4
Annual/pioneer
Nutrient cycling, hydrologic function, and/or soil stability have been severely altered, and possibly compromised. This is a highly variable state in which the specific plants observed will depend largely on the original community and the nature of the disturbance. This condition encompasses (but is not necessarily limited to) events such as severe fire impacts, heavy continuous grazing, heavy nutrient inputs, and abandoned cropland.
Dominant plant species
-
snow on the mountain (Euphorbia marginata), other herbaceous
-
ragweed (Ambrosia), other herbaceous
-
Texas croton (Croton texensis), other herbaceous
-
hoary verbena (Verbena stricta), other herbaceous
-
nightshade (Solanum), other herbaceous
-
thistle (Cirsium), other herbaceous
Community 4.1
Variable native and introduced
This community is heavily dominated by annual plants that thrive in disturbed areas and often includes snow-on-the-mountain, annual ragweed, Texas croton, nightshades, and/or hoary verbena. It is also particularly vulnerable to noxious weed invasion with the most common species being plumeless, musk, and Canada thistles. Leafy spurge becomes more common northward in the MLRA.
Dominant plant species
-
snow on the mountain (Euphorbia marginata), other herbaceous
-
ragweed (Ambrosia), other herbaceous
-
Texas croton (Croton texensis), other herbaceous
-
nightshade (Solanum), other herbaceous
-
hoary verbena (Verbena stricta), other herbaceous
-
thistle (Cirsium), other herbaceous
State 5
Deciduous overstory
Under historic disturbance regimes, frequent and uncontrolled fire and wildlife browsing served to keep woody species in check. However, in the absence of fire (either wild or prescribed), it's not uncommon for the woody trees and shrubs normally limited to riparian areas to expand into the floodplains, regardless of herbaceous community composition.
Dominant plant species
-
bur oak (Quercus macrocarpa), tree
-
boxelder (Acer negundo), tree
-
green ash (Fraxinus pennsylvanica), tree
-
sedge (Carex), grass
-
waterleaf (Hydrophyllum), other herbaceous
Community 5.1
Deciduous overstory
Deciduous woody species have encroached and established, typically with species such as bur oak, boxelder, and green ash. Eastern redcedar is not nearly as prominent as on upland sites, but may still occur. Moister, shaded growing conditions under the tree canopy causes a dramatic shift in understory composition towards species such as sedges, Virginia waterleaf, fowl mannagrass, and smooth Solomon’s seal.
Dominant plant species
-
bur oak (Quercus macrocarpa), tree
-
boxelder (Acer negundo), tree
-
green ash (Fraxinus pennsylvanica), tree
-
sedge (Carex), grass
-
waterleaf (Hydrophyllum), other herbaceous
Transition T1A
State 1 to 2
In the presence of introduced cool-season grasses, environmental conditions and/or management that reduces native vigor and stand resilience, and frees up resources (space, sunlight, nutrients, water) will allow for colonization of Kentucky bluegrass and smooth brome. Likewise, similar processes may also allow for deciduous woody shrubs and trees such as smooth sumac, roughleaf dogwood, and Siberian elm to expand.
Transition T1B
State 1 to 4
There are many possible triggers for this transition that may occur as acute events (e.g. plowing) or cumulative impacts of chronic events (e.g. long-term undermanaged grazing.) The absence of deep-rooted perennial cover exposes the site to topsoil loss, open nutrient cycle, and free space which collectively allow for opportunistic annual species to dominate.
Transition T1C
State 1 to 5
The presence of an invasion source coupled with fire exclusion allows cedar seeds to germinate and establish within the herbaceous stand. This typically begins near fencerows, woody draws, etc, and accelerates outward as propagules increase. Lack of intervening action allows cedar expansion to continue, and tree sizes to increase. Cedar will eventually modify site function in ways that promote further encroachment such as rainfall interception and stemflow, heavy duff litter, and shading of the herbaceous understory.
Restoration pathway R2A
State 2 to 1
Eradication of introduced cool-season grasses from this site will require long-term, targeted management efforts to create an adverse environment during the spring and late fall when bluegrass and brome are most actively growing, with favorable conditions during the summer to promote native warm-season species. Targeted practices such as prescribed burning, flash grazing, and herbicide are often employed at strategic times of the year to set back undesirable species. The combination of practices should strive to mimic the historic disturbance regimes to which the desirable native species are best adapted.
Transition T2A
State 2 to 3
If the conditions which initiated and fomented the colonization and expansion of cool-season invasion are not removed or mitigated, stand composition will continue to shift in this direction and begin to resemble a monoculture of bluegrass and/or brome. Due to the dense rhizomatous root mat of brome and bluegrass, native species suffer decreasing opportunities to contribute propagules, and individual plants lost are not replaced by desirable natives.
Transition T2B
State 2 to 4
There are many possible triggers for this transition that may occur as acute events (e.g. plowing) or cumulative impacts of chronic events (e.g. long-term undermanaged grazing.) The absence of deep-rooted perennial cover exposes the site to topsoil loss, open nutrient cycle, and free space which collectively allow for opportunistic annual species to dominate.
Transition T2C
State 2 to 5
The presence of an invasion source coupled with fire exclusion allows woody species to establish. This typically begins near fencerows, woody draws, etc, and accelerates outward as propagules increase. Lack of intervening action allows woody species expansion to continue, and tree sizes to increase.
Transition T3A
State 3 to 2
Aggressive intervening actions will be required to simultaneously recolonize native grasses and suppress vigor in undesirable species. Restoration follows the same principles as the R2A pathway, but may also require native range seeding if the latent seedbank is inadequate.
Transition T3B
State 3 to 4
Nutrient cycling, hydrologic function, and/or soil stability have been severely altered, and possibly compromised. This is a highly variable state in which the specific plants observed will depend largely on the original community and the nature of the disturbance.
Transition T3A
State 3 to 5
The presence of an invasion source coupled with fire exclusion allows cedar seeds to germinate and establish within the herbaceous stand. This typically begins near fencerows, woody draws, etc, and accelerates outward as propagules increase. Lack of intervening action allows cedar expansion to continue, and tree sizes to increase. Cedar will eventually modify site function in ways that promote further encroachment such as rainfall interception and stemflow, heavy duff litter, and shading of the herbaceous understory.
Transition R4A
State 4 to 1
With favorable weather and site stability, it may take just a few years for the site to naturally return to a perennial community. Range seeding can “jump start” the recolonization of desirable species and may re-establish a near reference grass community; although, forb diversity may take longer to recover. Depending on the nature of the disturbance(s), additional ameliorative efforts may be necessary to mitigate accelerated erosion and weedy competition until the seeded perennial community has stabilized. It is possible for a disturbance and/or subsequent processes (e.g. accelerated erosion) to profoundly, and even permanently, alter fundamental soil properties in such a way that the site may never again exhibit its historic structure or function without extraordinary restoration inputs.
Restoration pathway R5A
State 5 to 1
Tree mortality is required to restore a grassland state, however the herbaceous response will depend on many factors such as method(s) used, mortality rates, and the remnant herbaceous species. Mechanical and chemical methods can remove cedars but will have little if any notable impact on the herbs. Reintroducing the historic fire regime will provide the most profound and beneficial effects, and seasonal timing and burn intensity can have significant influence on the herbaceous outcome. As a general rule, hot spring burns will not only kill trees but also stress shallower-rooted invasive cool-season grasses and promote a ahift in favor of the reference community.
Additional community tables
Table 6. Community 1.1 plant community composition
Group | Common name | Symbol | Scientific name | Annual production (lb/acre) | Foliar cover (%) | |
---|---|---|---|---|---|---|
Grass/Grasslike
|
||||||
1 | Tall warm-season | 2560–2880 | ||||
big bluestem | ANGE | Andropogon gerardii | 640–1120 | – | ||
switchgrass | PAVI2 | Panicum virgatum | 160–480 | – | ||
Indiangrass | SONU2 | Sorghastrum nutans | 160–320 | – | ||
composite dropseed | SPCO16 | Sporobolus compositus | 0–175 | – | ||
2 | Mid warm-season | 480–960 | ||||
little bluestem | SCSC | Schizachyrium scoparium | 320–640 | – | ||
sideoats grama | BOCU | Bouteloua curtipendula | 160–320 | – | ||
3 | Cool-season | 160–640 | ||||
western wheatgrass | PASM | Pascopyrum smithii | 160–640 | – | ||
Scribner's rosette grass | DIOLS | Dichanthelium oligosanthes var. scribnerianum | 0–160 | – | ||
Canada wildrye | ELCA4 | Elymus canadensis | 0–160 | – | ||
prairie Junegrass | KOMA | Koeleria macrantha | 0–160 | – | ||
4 | Grass-like | 160–320 | ||||
sedge | CAREX | Carex | 160–320 | – | ||
Forb
|
||||||
5 | Forb | 160–320 | ||||
meadow garlic | ALCA3 | Allium canadense | 0–96 | – | ||
Cuman ragweed | AMPS | Ambrosia psilostachya | 0–96 | – | ||
white sagebrush | ARLU | Artemisia ludoviciana | 0–96 | – | ||
false boneset | BREU | Brickellia eupatorioides | 0–96 | – | ||
purple poppymallow | CAIN2 | Callirhoe involucrata | 0–96 | – | ||
purple prairie clover | DAPU5 | Dalea purpurea | 0–96 | – | ||
Illinois ticktrefoil | DEIL2 | Desmodium illinoense | 0–96 | – | ||
dotted blazing star | LIPU | Liatris punctata | 0–96 | – | ||
silverleaf Indian breadroot | PEAR6 | Pediomelum argophyllum | 0–96 | – | ||
blackeyed Susan | RUHI2 | Rudbeckia hirta | 0–96 | – | ||
Missouri goldenrod | SOMI2 | Solidago missouriensis | 35–96 | – | ||
white heath aster | SYER | Symphyotrichum ericoides | 0–96 | – | ||
Baldwin's ironweed | VEBA | Vernonia baldwinii | 0–96 | – | ||
hoary verbena | VEST | Verbena stricta | 0–96 | – | ||
Shrub/Vine
|
||||||
7 | Shrubs | 0–160 | ||||
Shrub (>.5m) | 2SHRUB | Shrub (>.5m) | 0–160 | – | ||
leadplant | AMCA6 | Amorpha canescens | 0–160 | – | ||
prairie rose | ROAR3 | Rosa arkansana | 0–160 | – | ||
western snowberry | SYOC | Symphoricarpos occidentalis | 0–160 | – | ||
eastern poison ivy | TORA2 | Toxicodendron radicans | 0–160 | – |
Interpretations
Animal community
This site is well adapted to managed grazing by domestic livestock. The predominance of herbaceous plants across all plant community phases best lends these sites to grazing by cattle but browsing livestock such as goats or sheep that will more heavily utilize invasive forbs and brush. Carrying capacity and production estimates are conservative estimates that should be used only as guidelines in initial stages of grazing lands planning.
Often, the plant community does not entirely match any particular plant community (as described in the ecological site description). Because of this, a resource inventory is necessary to document plant composition and production. Proper interpretation of this inventory data will permit the establishment of a safe, initial stocking rate for the type and class of animals and level of grazing management. 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.
Suggested stocking rates (carrying capacity*) for cattle under continuous season-long grazing under normal growing conditions are listed below:
- 1.1 Big bluestem-Little bluestem; 3200 lbs/acre production and 0.88 AUM/acre
- 1.2 Sideoats grama-Composite dropseed; 2600 lbs/acre production and 0.71 AUM/acre
- 2.1 Subdominant smooth brome-KY bluegrass; 2500 lbs/acre production and 0.69 AUM/acre
- 2.2 Codominant smooth brome-KY bluegrass; 2350 lbs/ac and 0.64 AUM/acre with 50% or more introduced cool-season component
- 3.1 Smooth brome-KY bluegrass; 2400 lbs/ac and .66 AUM/ac, unfertilized, non-irrigated naturalized community. Refer to Forage Suitability Groups for cool-season pasture under a higher management level.
*Carrying capacity based on continuous season-long grazing by cattle under average growing conditions, 25% harvest efficiency. Air dry forage requirements based on 3% of animal body weight, or 912 lbs/AU/month.
If grazing distribution problems occur, stocking rates must be reduced to maintain plant health and vigor. Carrying capacity and production estimates are conservative estimates that should be used only as guidelines in the initial stages of the conservation planning process. Utilizing a rotational grazing system that allows for adequate rest and recovery will increase plant vigor and carrying capacity. 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 to document plant composition and production. More precise carrying capacity estimates can be calculated based on actual site information along with animal preference data, particularly when livestock 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.
Supporting information
Inventory data references
Primary author: Greg Clark (Greg.Clark@usda.gov) Soil Survey Office Leader, USDA-NRCS, Stanton NE
Information presented here has been derived from RANGE-417 archives, Rangeland NRI, and other inventory data. Field observations from range-trained personnel were also used. In addition to the multitude of NRCS field office employees and private landowners that helped with site visits and local knowledge, those involved in developing this site include:
Nebraska NRCS:
Nadine Bishop, State Rangeland Management Specialist
Patrick Cowsert, Resource Soil Scientist
Cassidy Gerdes, Biologist
Dirk Schultz, Soil Conservationist
Dan Shurtliff, Asst State Soil Scientist
South Dakota NRCS:
Stan Boltz, State Rangeland Management Specialist
Shane Deranleau, Area Rangeland Management Specialist
Kevin Luebke, State Biologist
Iowa NRCS:
Jess Jackson, Area Grazing Specialist
Minnesota NRCS:
Lance Smith, Area Grazing Specialist
MLRA Office 10:
Stu McFarland, Ecological Site Inventory Specialist, QC
Stacey Clark, Ecological Site Inventory Specialist, QA
Michael Whited, Soil Data Quality Specialist
Jo Parsley, Soil Scientist/10-3 MSSO Leader
National Soil Survey Center:
Mike Kucera, National Agronomist, Soil Quality & Ecosystems
Steve Peaslee, GIS Specialist, Soil Survey Interpretations
Nebraska Game & Parks Commission:
Gerry Steinauer, Botanist
Scott Wessel, Biologist
Russ Hamer, Biologist
Rebekah Jessen, Biologist
Nebraska Forest Service:
Steve Rasmussen, District Forester
Other references
Bestelmeyer, Brandon, et al. 2010. Practical Guidance for Developing State-and-transition Models. Rangelands 32:6 pp 2-64. Wheat Ridge, CO: Society for Range Management.
Fenneman, Nevin M. 1916. Physiographic Subdivision of the United States. Annals of the Association of American Geographers.
Helzer, Chris. 2010. The Ecology and Management of Prairies in the Central U.S. Iowa City, IA: University of Iowa Press/The Nature Conservancy.
Kaul, Robert B., David Sutherland, and Steven Rolfsmeier. 2006. The Flora of Nebraska. Lincoln, NE: University of Nebraska – Lincoln (Conservation and Survey Division, School of Natural Resources.)
NOAA/UNL – High Plains Regional Climate Center. Historical Data Summaries: http://www.hprcc.unl.edu/data/historical/
Omernik, J.M. 1997. Ecoregions of the Conterminous United States. Annals of the Association of American Geographers, v.77, no. 1, p.118-125.
Steinauer, Gerry and Steve Rolfsmeier. 2010. Terrestrial Ecological Systems and Natural Communities of Nebraska. Lincoln, NE: Nebraska Natural Heritage Program and Nebraska Game and Parks Commission.
USDA/USFS. 2007. Ecological Subregions: Sections and Subsections for the Conterminous United States. Washington, DC: USDA - Forest Service.
USDA/SCS. 1977. Rangeland Resources of Nebraska. Lincoln, NE: Society for Range Management. USDA/NRCS. 2011. ESD User Guide. Fort Worth, TX: Central National Technology Support Center.
USDA/NRCS 2006. Land Resource Regions and Major Land Resource Areas of the United States, the Caribbean, and the Pacific Basin. U.S. Department of Agriculture Handbook 296.
USDA/NRCS. 2012. Field Office Technical Guide (Nebraska, Natural Resources Information, Statewide Soil and Site Information, Rangeland Interpretations, Nebraska Range Site Descriptions – Vegetative Zones 3 and 4), U.S. Department of Agriculture, Natural Resources Conservation Service, Nebraska Ecological Sciences.
Contributors
Greg Clark (Greg.Clark@usda.gov) Soil Survey Office Leader, USDA-NRCS, Stanton NE
Stu McFarland
Approval
Suzanne Mayne-Kinney, 6/28/2024
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) | Stu McFarland, Nadine Bishop |
---|---|
Contact for lead author | |
Date | 08/01/2013 |
Approved by | Suzanne Mayne-Kinney |
Approval date | |
Composition (Indicators 10 and 12) based on | Annual Production |
Indicators
-
Number and extent of rills:
None. -
Presence of water flow patterns:
None. -
Number and height of erosional pedestals or terracettes:
None. -
Bare ground from Ecological Site Description or other studies (rock, litter, lichen, moss, plant canopy are not bare ground):
<5% as very small (<3”) patches, however, bare ground can be expected to be much higher if litter has been consumed by recent fire. -
Number of gullies and erosion associated with gullies:
None. -
Extent of wind scoured, blowouts and/or depositional areas:
None. -
Amount of litter movement (describe size and distance expected to travel):
None. -
Soil surface (top few mm) resistance to erosion (stability values are averages - most sites will show a range of values):
Soil stability rating of 6 -
Soil surface structure and SOM content (include type of structure and A-horizon color and thickness):
A mollic epipedon is present. Refer to the Official Series Description for the range of characteristics of site-specific soils. -
Effect of community phase composition (relative proportion of different functional groups) and spatial distribution on infiltration and runoff:
Robust herbaceous canopy provides nearly 100% coverage reducing raindrop energy, and abundant litter slows overland flow for improved infiltration. -
Presence and thickness of compaction layer (usually none; describe soil profile features which may be mistaken for compaction on this site):
None. -
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:
warm-season tallgrasses >Sub-dominant:
warm-season midgrasses >Other:
cool-season grasses = grasslikes = forbs > shrubsAdditional:
-
Amount of plant mortality and decadence (include which functional groups are expected to show mortality or decadence):
Very little to no evidence of perennial decadence or mortality. -
Average percent litter cover (%) and depth ( in):
However, litter cover could be much lower if consumed by recent fire. -
Expected annual annual-production (this is TOTAL above-ground annual-production, not just forage annual-production):
Production ranges from 2,600 - 3,700 lbs/ac (air-dry weight) depending on climatic conditions. The reference representative value production is 3,200 lbs/ac (air-dry weight). -
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:
Eastern redcedar, Kentucky bluegrass, smooth brome, plumeless thistle, musk thistle, Canada thistle, smooth sumac, roughleaf dogwood, buckbrush, and Siberian elm are some of the more common invaders. Other species of concern that may be encountered include: absinth wormwood, sulfur cinquefoil, downy and Japanese brome, perennial sow thistle, spotted and diffuse knapweeds, and Autumn olive. Refer to state and county weed agencies for a comprehensive list. -
Perennial plant reproductive capability:
Flowering, seed production, and rhizomatous/stoloniferous growth are apparent and not hindered by plant stress/reduced vigor.
Print Options
Sections
Font
Other
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 2 (additional transitions)
T1A | - | Non-native grasses increase |
---|---|---|
T1B | - | Disturbance; annual species dominant |
T1C | - | Woody species dominate |
R2A | - | Restoration inputs; native warm season grasses dominate |
T2A | - | Increasing dominance of cool season grasses |
T2B | - | Disturbance; annual species dominant |
T2C | - | Woody species dominate |
T3A | - | Management inputs; increase of warm season grasses |
T3B | - | Cool season grasses dominate the site |
T3A | - | Woody species continue to increase and dominant the site |
R4A | - | Restoration inputs; warm season grasses dominant |
R5A | - | Restoration inputs to promote warm season grasses |
State 1 submodel, plant communities
1.1A | - | Intense grazing with inadequate recover periods |
---|---|---|
1.2A | - | Grazing management with adequate recovery periods |
State 2 submodel, plant communities
2.1A | - | Increasing dominance of non-native grasses |
---|---|---|
2.2A | - | Management to promote warm-season grasses |