Shallow Limy
Scenario model
Current ecosystem state
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Management practices/drivers
Select a transition or restoration pathway
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Transition T1A
Heavy grazing or haying with inadequate growing season recovery periods.
More details -
Transition T1B
Woody encroachment and no fire or woody species management.
More details -
Transition T2A
Woody encroachment and no fire or woody species management.
More details -
Restoration pathway R3A
Prescribed burning, wildfire, timber harvest, and brush management.
More details -
Restoration pathway R3B
Prescribed burning, wildfire, timber harvest, and brush management.
More details -
No transition or restoration pathway between the selected states has been described
Target ecosystem state
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State 1
Reference State
Description
The Reference State (1) describes the range of vegetative community phases that occur on the Shallow Limy ecological site where the natural processes are mostly intact. The Reference Community (1.1) is a representation of the native plant community phase that occupies a site that has been minimally altered by management. The Degraded Native Grass (1.2), the At-Risk (1.3), and the Excessive Litter (1.4) Communities are the phases that result from management decisions that are unfavorable for a healthy Reference Community (1.1). High perennial grass cover and production allows for increased soil moisture retention, vegetative production, and overall soil quality.
Submodel
Description
The Native/Invaded Grass State (2) exhibits a co-dominance of both native and introduced species. Native, warm-season tall grasses, such as big bluestem and Indiangrass, may be present as trace functional group. The plant community consists of the more grazing tolerant native species and a significant component of introduced, cool-season grasses such as smooth brome, tall fescue, and Kentucky bluegrass. Forb diversity is limited to species with low palatability. Plant diversity is low. The Shortgrass Sod/Invaded Grass Community (2.1) is the component of the Native/Invaded Grass State (2).
The loss of warm-season, tall and mid 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 grazing evasive plant communities. Impaired energy capture and altered hydrologic function are reflected in reduced vegetative productivity, shallower rooting depth and degraded soil quality. Continuous and heavy grazing pressure will maintain this plant community in a sod bound condition. Grazing management practices that allow for adequate periods of recovery between grazing events and grazing timed early and late during the growing season will reduce the vigor of the nonnative cool-season grasses and may allow the warm-season tall and mid grasses to increase in abundance and productivity. Return to the Reference State (1) is unlikely due to the loss of plant diversity, overall soil disturbance, and alterations to hydrology.
Submodel
Description
The Invaded Woody State (3) is the result of woody encroachment. Once the tree canopy cover reaches 15 percent with an average tree height exceeding five feet, the threshold is crossed. Woody species are encroaching due to lack of prescribed fire and other brush management practices. Typical ecological impacts are a loss of native grasses, degraded forage productivity, and reduced soil quality. This state consists of the Invaded Woody Community (3.1).
Prescribed burning, wildfire, timber harvest and brush management will move this state toward a grass dominated state. If the Invaded Woody State (3) transitioned from the Native/Invaded Grass State (2), the land cannot be restored to the Reference State (1) as the native plant community, soils, and hydrologic function had been too severely impacted prior to the woody encroachment to allow restoration to the Reference State (1).
Submodel
Mechanism
Heavy grazing or haying with inadequate growing season recovery periods (deferment) will cause the Reference State (1) to lose a significant proportion of warm-season, tall and mid grass species and cross a threshold to the Native/Invaded Grass State (2). Water infiltration and other hydrologic functions will be 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 catastrophically degraded to the point that recovery is unlikely. Once this occurs, it is highly unlikely that grazing management alone will return the community to the Reference State (1).
Mechanism
Disruption of natural fire regime and encroachment of exotic and invasive native woody species with no woody species management will cause the Reference State (1) to shift to the Invaded Woody State (3).
Mechanism
Disruption of natural fire regime and encroachment of exotic and invasive native woody species will shift the Native/Invaded Grass State (2) to the Invaded Woody State (3).
Mechanism
Prescribed burning, wildfire, timber harvest, and brush management will move the Invaded Woody State (3) toward the Reference State (1). The forb component of a site with heavy tree density or canopy cover may initially increase following tree removal through mechanical brush management treatments and prescribed fire. If resprouting brush is present, stumps must be chemically treated immediately after mechanical 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 (4).
Land that transitioned to the Invaded Woody State (4) from the Native/Invaded Grass State (2) cannot be restored to the Reference State (1) through removal of woody species.
Relevant conservation practices
| Practice | External resources |
|---|---|
|
Brush Management |
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Prescribed Burning |
Mechanism
Prescribed burning, wildfire, timber harvest, and brush management will move the Invaded Woody State (3) toward the Native/Invaded Grass State (2). The forb component of a site with heavy tree density or canopy cover may initially increase following tree removal through mechanical brush management treatments and prescribed fire. If resprouting brush is present, stumps must be chemically treated immediately after mechanical 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 (4).
Land that transitioned to the Invaded Woody State (4) from the Native/Invaded Grass State (2) cannot be restored to the Reference State (1) through removal of woody species.
Relevant conservation practices
| Practice | External resources |
|---|---|
|
Brush Management |
|
|
Prescribed Burning |
Model keys
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