State and transition model
State 1
1 Reference State
This site is a grassland community with scattered shrubs and a few forbs. The grasses are a mixture of cool and warm season grasses. The shrubs are fourwing saltbush at the lower elevation and precipitation areas and Wyoming big sagebrush at the higher elevation and precipitation areas.
Community 1.1
1.1 Grassland with scattered shrubs (HCPC)
The historic climax plant community consists of mid and short grasses with a small percentage of shrubs, half shrubs and forbs. Common plant species include: blue grama, needle and thread, western wheatgrass,muttongrass, fourwing saltbush and Wyoming big sagebrush.
Community 1.2
1.2 Decreased grasses and increased shrubs/trees/forbs
Disturbance has deteriorated the site. There is a significant loss of perennial native grasses. Shrubs increase on the site and annual grasses and forbs increase. Juniper can invade from nearby upland sites. Plants that increase or invade: fourwing saltbush, Wyoming big sagebrush, broom snakeweed, rabbitbrush, juniper.
Pathway 1.1A
Community 1.1 to 1.2
Repetitive, high utilization of palatable grasses have given shrubs a competitive advantage.
Pathway 1.2A
Community 1.2 to 1.1
A set-back to the shrubs such as fire along with improved management to increase composition of palatable grasses.
State 2
2 Native/Introduced Annuals State
The plant communities in this state are similar to those in the reference state. Non-native annuals are now present in the plant communities and compete with the native species. Disturbances such as fire or drought may allow these non-native species to increase their dominance on the site.
Community 2.1
2.1 Grassland and scattered shrubs with introduced non-native annuals.
This plant community consists of mid and short grasses with a small percentage of shrubs, half shrubs and forbs. Common plant species include: blue grama, needle and thread, western wheatgrass, muttongrass, fourwing saltbush and Wyoming big sagebrush. Non-native annual grasses and forbs are part of the plant community. Cheatgrass and Russian thistle are common non-native plants found on the site.
Community 2.2
2.2 Increased shrubs/trees-decreased grass and non-native plants
There is a significant loss of perennial native grasses. Shrubs increase on the site and annual grasses and forbs increase. Juniper can invade from nearby upland sites. Plants that increase or invade: fourwing saltbush, Wyoming big sagebrush, broom snakeweed, rabbitbrush, juniper. Non-native annual grasses and forbs are part of the plant commmunity. Cheatgrass and Russian thistle are common examples.
Pathway 2.1A
Community 2.1 to 2.2
Repetitive, high utilization of palatable grass species giving shrubs a competitive advantage.
Pathway 2.2A
Community 2.2 to 2.1
A set-back to the shrubs such as fire along with improved management to increase composition of palatable grasses.
Transition T1A
State 1 to 2
Invasion of introduced species.
Restoration pathway R2A
State 2 to 1
Once introduced species have invaded it is unlikely the site can return to reference.