Stony Clay Loam 30-38" PZ
Scenario model
Current ecosystem state
Select a state
Management practices/drivers
Select a transition or restoration pathway
- Transition T1A More details
- Transition T1B More details
- Restoration pathway R2A More details
- Transition T2A More details
- Restoration pathway R3A More details
- Restoration pathway R3B More details
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No transition or restoration pathway between the selected states has been described
Target ecosystem state
Select a state
State 1
Prairie State - Reference
Submodel
Mechanism
Excessive grazing and/or extended severe drought will eventually result in almost complete loss of the tallgrass and a severe decline of higher successional midgrass species on this site. They are replaced by shortgrasses, lower successional midgrasses, less palatable forbs, and annuals. The driver for transition T1A for the herbaceous component is improper grazing management.
Mechanism
The grassland states and plant communities are resistant to shrub dominance. However, shrubs are present in minor amounts in those states and communities, therefore propagules are present. Even with proper grazing and favorable climate conditions, lack of fire or brush control for over 25 years will allow woody species to encroach from adjacent sites and allow endemic woody species to increase in canopy to reach the 30% threshold level. Once canopy cover reaches 15% the transition to the mixed brush state has begun. Canopy cover of 30% indicates that the transition has occurred. Improper grazing management, prolonged drought, and a warming climate will provide a competitive advantage to shrubs which will accelerate this process. This transition can occur from any of the grassland states and plant communities. The drivers for this transition are excessive grazing as well as lack of fire and/or brush control. Introduction of aggressive woody invader species (i.e. mesquite or juniper) increase the risk that this state transition will occur and accelerate the rate at which it is likely to occur. The driver for this transition is lack of fire and/or brush control.
Mechanism
The Shortgrass/Midgrass State will require range planting accompanied by return to the proper grazing management that includes proper stocking rates and sufficient critical growing season deferment in combination with proper grazing intensity in order to return to the Tallgrass State. Favorable moisture conditions will facilitate or accelerate this transition. The driver for the herbaceous component is proper grazing management.
Relevant conservation practices
| Practice | External resources |
|---|---|
|
Prescribed Grazing |
Mechanism
The grassland states and plant communities are resistant to shrub dominance. However, shrubs are present in minor amounts in those states and communities, therefore propagules are present. Even with proper grazing and favorable climate conditions, lack of fire or brush control for over 25 years will allow woody species to encroach from adjacent sites and allow endemic woody species to increase in canopy to reach the 30% threshold level. Once canopy cover reaches 15% the transition to the mixed brush state has begun. Canopy cover of 30% indicates that the transition has occurred. Improper grazing management, prolonged drought, and a warming climate will provide a competitive advantage to shrubs which will accelerate this process. This transition can occur from any of the grassland states and plant communities. The drivers for this transition are excessive grazing as well as lack of fire and/or brush control. Introduction of aggressive woody invader species (i.e. mesquite or juniper) increase the risk that this state transition will occur and accelerate the rate at which it is likely to occur. The driver for this transition is improper grazing management as well as lack of fire and/or brush control.
A system of brush management and fire can reduce the woody component below the transition level of 30% canopy. Managers may chose to leave some brush for wildlife habitat objectives. Continued fire and/or brush management will be required to maintain woody density and canopy below the threshold. If the herbaceous component has transitioned to shortgrasses and low forbs, proper grazing management (combined with favorable moisture conditions and adequate seed source) will be necessary to facilitate the shift of the understory component to a midgrass-dominated plant community. Range planting may accelerate the transition of the herbaceous community, particularly when combined with favorable growing conditions.
Mechanism
Restoration of the Mixed Brush State to the Tallgrass Prairie State requires substantial energy input. Mechanical or chemical brush control treatments can be used to remove woody species. A long-term prescribed fire program may sufficiently reduce brush density to a level below the threshold of the Mixed Brush State, particularly if the woody component is dominated by species that are not re-sprouters. However, fire may not be sufficient to remove mature trees. A mixed program consisting of mechanical, chemical, and fire measures may be used. Brush control in combination with prescribed fire, proper grazing management, and favorable growing conditions may be the most economical means of creating and maintaining the desired plant community. If remnant populations of tallgrasses, midgrasses, and desirable forbs are not present at sufficient levels, range planting will be necessary to restore the reference plant community. Depending on the understory community and inputs of seed, the restoration pathway can result in a return to any of the Grassland State Communities. The driver for Restoration Pathway R3A is fire and/or brush control combined with restoration of the herbaceous community and proper grazing management. Restoration may require aggressive treatment of invader species.
Relevant conservation practices
| Practice | External resources |
|---|---|
|
Brush Management |
|
|
Prescribed Burning |
|
|
Prescribed Grazing |
Mechanism
Restoration of the Mixed Brush State to the Shortgrass/Midgrass Prairie State requires substantial energy input. Mechanical or herbicidal brush control treatments can be used to remove woody species. A long-term prescribed fire program may sufficiently reduce brush density to a level below the threshold of the Mixed Brush State, particularly if the woody component is dominated by species that are not re-sprouters. However, fire may not be sufficient to remove mature trees. A mixed program consisting of mechanical, chemical, and fire measures may be used. Brush control in combination with prescribed fire, proper grazing management, and favorable growing conditions may be the most economical means of creating and maintaining the desired plant community. The driver for Restoration Pathway R3B is fire and/or brush control combined with restoration of the herbaceous community and proper grazing management. Restoration may require aggressive treatment of invader species.
Relevant conservation practices
| Practice | External resources |
|---|---|
|
Brush Management |
|
|
Prescribed Burning |
|
|
Prescribed Grazing |
Model keys
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